Merge remote-tracking branch 'upstream/master'

Conflicts:
	perl6.html.markdown

bash.html.markdown

@@ -10,6 +10,7 @@ contributors:
     - ["Anton Strömkvist", "http://lutic.org/"]
     - ["Rahil Momin", "https://github.com/iamrahil"]
     - ["Gregrory Kielian", "https://github.com/gskielian"]
+    - ["Etan Reisner", "https://github.com/deryni"]
 filename: LearnBash.sh
 ---
 
@@ -31,32 +32,41 @@ echo Hello world!
 echo 'This is the first line'; echo 'This is the second line'
 
 # Declaring a variable looks like this:
-VARIABLE="Some string"
+Variable="Some string"
 
 # But not like this:
-VARIABLE = "Some string"
+Variable = "Some string"
-# Bash will decide that VARIABLE is a command it must execute and give an error
+# Bash will decide that Variable is a command it must execute and give an error
-# because it couldn't be found.
+# because it can't be found.
+
+# Or like this:
+Variable= 'Some string'
+# Bash will decide that 'Some string' is a command it must execute and give an
+# error because it can't be found. (In this case the 'Variable=' part is seen
+# as a variable assignment valid only for the scope of the 'Some string'
+# command.)
 
 # Using the variable:
-echo $VARIABLE
+echo $Variable
-echo "$VARIABLE"
+echo "$Variable"
-echo '$VARIABLE'
+echo '$Variable'
 # When you use the variable itself — assign it, export it, or else — you write
 # its name without $. If you want to use variable's value, you should use $.
 # Note that ' (single quote) won't expand the variables!
 
 # String substitution in variables
-echo ${VARIABLE/Some/A}
+echo ${Variable/Some/A}
-# This will substitute the first occurance of "Some" with "A"
+# This will substitute the first occurrence of "Some" with "A"
 
 # Substring from a variable
-echo ${VARIABLE:0:7}
+Length=7
+echo ${Variable:0:Length}
 # This will return only the first 7 characters of the value
 
 # Default value for variable
-echo ${FOO:-"DefaultValueIfFOOIsMissingOrEmpty"}
+echo ${Foo:-"DefaultValueIfFooIsMissingOrEmpty"}
-# This works for null (FOO=), empty string (FOO=""), zero (FOO=0) returns 0
+# This works for null (Foo=) and empty string (Foo=""); zero (Foo=0) returns 0.
+# Note that it only returns default value and doesn't change variable value.
 
 # Builtin variables:
 # There are some useful builtin variables, like
@@ -64,16 +74,16 @@ echo "Last program return value: $?"
 echo "Script's PID: $$"
 echo "Number of arguments: $#"
 echo "Scripts arguments: $@"
-echo "Scripts arguments seperated in different variables: $1 $2..."
+echo "Scripts arguments separated in different variables: $1 $2..."
 
 # Reading a value from input:
 echo "What's your name?"
-read NAME # Note that we didn't need to declare a new variable
+read Name # Note that we didn't need to declare a new variable
-echo Hello, $NAME!
+echo Hello, $Name!
 
 # We have the usual if structure:
 # use 'man test' for more info about conditionals
-if [ $NAME -ne $USER ]
+if [ $Name -ne $USER ]
 then
     echo "Your name isn't your username"
 else
@@ -85,14 +95,14 @@ echo "Always executed" || echo "Only executed if first command fails"
 echo "Always executed" && echo "Only executed if first command does NOT fail"
 
 # To use && and || with if statements, you need multiple pairs of square brackets:
-if [ $NAME == "Steve" ] && [ $AGE -eq 15 ]
+if [ $Name == "Steve" ] && [ $Age -eq 15 ]
 then
-    echo "This will run if $NAME is Steve AND $AGE is 15."
+    echo "This will run if $Name is Steve AND $Age is 15."
 fi
 
-if [ $NAME == "Daniya" ] || [ $NAME == "Zach" ]
+if [ $Name == "Daniya" ] || [ $Name == "Zach" ]
 then
-    echo "This will run if $NAME is Daniya OR Zach."
+    echo "This will run if $Name is Daniya OR Zach."
 fi
 
 # Expressions are denoted with the following format:
@@ -134,7 +144,7 @@ python hello.py > /dev/null 2>&1
 # if you want to append instead, use ">>":
 python hello.py >> "output.out" 2>> "error.err"
 
-# Overwrite output.txt, append to error.err, and count lines:
+# Overwrite output.out, append to error.err, and count lines:
 info bash 'Basic Shell Features' 'Redirections' > output.out 2>> error.err
 wc -l output.out error.err
 
@@ -142,7 +152,7 @@ wc -l output.out error.err
 # see: man fd
 echo <(echo "#helloworld")
 
-# Overwrite output.txt with "#helloworld":
+# Overwrite output.out with "#helloworld":
 cat > output.out <(echo "#helloworld")
 echo "#helloworld" > output.out
 echo "#helloworld" | cat > output.out
@@ -161,7 +171,7 @@ echo "There are $(ls | wc -l) items here."
 echo "There are `ls | wc -l` items here."
 
 # Bash uses a case statement that works similarly to switch in Java and C++:
-case "$VARIABLE" in 
+case "$Variable" in
     #List patterns for the conditions you want to meet
     0) echo "There is a zero.";;
     1) echo "There is a one.";;
@@ -169,10 +179,10 @@ case "$VARIABLE" in
 esac
 
 # for loops iterate for as many arguments given:
-# The contents of $VARIABLE is printed three times.
+# The contents of $Variable is printed three times.
-for VARIABLE in {1..3}
+for Variable in {1..3}
 do
-    echo "$VARIABLE"
+    echo "$Variable"
 done
 
 # Or write it the "traditional for loop" way:
@@ -183,16 +193,16 @@ done
 
 # They can also be used to act on files..
 # This will run the command 'cat' on file1 and file2
-for VARIABLE in file1 file2
+for Variable in file1 file2
 do
-    cat "$VARIABLE"
+    cat "$Variable"
 done
 
 # ..or the output from a command
 # This will cat the output from ls.
-for OUTPUT in $(ls)
+for Output in $(ls)
 do
-    cat "$OUTPUT"
+    cat "$Output"
 done
 
 # while loop:
@@ -220,7 +230,7 @@ bar ()
 }
 
 # Calling your function
-foo "My name is" $NAME
+foo "My name is" $Name
 
 # There are a lot of useful commands you should learn:
 # prints last 10 lines of file.txt

c++.html.markdown

@@ -32,8 +32,7 @@ one of the most widely-used programming languages.
 // variable declarations, primitive types, and functions.
 
 // Just like in C, your program's entry point is a function called
-// main with an integer return type,
+// main with an integer return type.
-// though void main() is also accepted by most compilers (gcc, clang, etc.)
 // This value serves as the program's exit status.
 // See http://en.wikipedia.org/wiki/Exit_status for more information.
 int main(int argc, char** argv)
@@ -289,7 +288,7 @@ public:
 
     // Functions can also be defined inside the class body.
     // Functions defined as such are automatically inlined.
-    void bark() const { std::cout << name << " barks!\n" }
+    void bark() const { std::cout << name << " barks!\n"; }
 
     // Along with constructors, C++ provides destructors.
     // These are called when an object is deleted or falls out of scope.
@@ -301,7 +300,7 @@ public:
 }; // A semicolon must follow the class definition.
 
 // Class member functions are usually implemented in .cpp files.
-void Dog::Dog()
+Dog::Dog()
 {
     std::cout << "A dog has been constructed\n";
 }
@@ -324,7 +323,7 @@ void Dog::print() const
     std::cout << "Dog is " << name << " and weighs " << weight << "kg\n";
 }
 
-void Dog::~Dog()
+Dog::~Dog()
 {
     cout << "Goodbye " << name << "\n";
 }
@@ -333,7 +332,7 @@ int main() {
     Dog myDog; // prints "A dog has been constructed"
     myDog.setName("Barkley");
     myDog.setWeight(10);
-    myDog.printDog(); // prints "Dog is Barkley and weighs 10 kg"
+    myDog.print(); // prints "Dog is Barkley and weighs 10 kg"
     return 0;
 } // prints "Goodbye Barkley"
 
@@ -342,7 +341,7 @@ int main() {
 // This class inherits everything public and protected from the Dog class
 class OwnedDog : public Dog {
 
-    void setOwner(const std::string& dogsOwner)
+    void setOwner(const std::string& dogsOwner);
 
     // Override the behavior of the print function for all OwnedDogs. See
     // http://en.wikipedia.org/wiki/Polymorphism_(computer_science)#Subtyping
@@ -426,13 +425,92 @@ int main () {
     Point up (0,1);
     Point right (1,0);
     // This calls the Point + operator
-    // Point up calls the + (function) with right as its paramater
+    // Point up calls the + (function) with right as its parameter
     Point result = up + right;
     // Prints "Result is upright (1,1)"
     cout << "Result is upright (" << result.x << ',' << result.y << ")\n";
     return 0;
 }
 
+/////////////////////
+// Templates
+/////////////////////
+
+// Templates in C++ are mostly used for generic programming, though they are
+// much more powerful than generics constructs in other languages. It also
+// supports explicit and partial specialization, functional-style type classes,
+// and also it's Turing-complete.
+
+// We start with the kind of generic programming you might be familiar with. To
+// define a class or function that takes a type parameter:
+template<class T>
+class Box {
+public:
+    // In this class, T can be used as any other type.
+    void insert(const T&) { ... }
+};
+
+// During compilation, the compiler actually generates copies of each template
+// with parameters substituted, and so the full definition of the class must be
+// present at each invocation. This is why you will see template classes defined
+// entirely in header files.
+
+// To instantiate a template class on the stack:
+Box<int> intBox;
+
+// and you can use it as you would expect:
+intBox.insert(123);
+
+// You can, of course, nest templates:
+Box<Box<int> > boxOfBox;
+boxOfBox.insert(intBox);
+
+// Up until C++11, you must place a space between the two '>'s, otherwise '>>'
+// will be parsed as the right shift operator.
+
+// You will sometimes see
+//   template<typename T>
+// instead. The 'class' keyword and 'typename' keyword are _mostly_
+// interchangeable in this case. For full explanation, see
+//   http://en.wikipedia.org/wiki/Typename
+// (yes, that keyword has its own Wikipedia page).
+
+// Similarly, a template function:
+template<class T>
+void barkThreeTimes(const T& input)
+{
+    input.bark();
+    input.bark();
+    input.bark();
+}
+
+// Notice that nothing is specified about the type parameters here. The compiler
+// will generate and then type-check every invocation of the template, so the
+// above function works with any type 'T' that has a const 'bark' method!
+
+Dog fluffy;
+fluffy.setName("Fluffy")
+barkThreeTimes(fluffy); // Prints "Fluffy barks" three times.
+
+// Template parameters don't have to be classes:
+template<int Y>
+void printMessage() {
+  cout << "Learn C++ in " << Y << " minutes!" << endl;
+}
+
+// And you can explicitly specialize templates for more efficient code. Of
+// course, most real-world uses of specialization are not as trivial as this.
+// Note that you still need to declare the function (or class) as a template
+// even if you explicitly specified all parameters.
+template<>
+void printMessage<10>() {
+  cout << "Learn C++ faster in only 10 minutes!" << endl;
+}
+
+printMessage<20>();  // Prints "Learn C++ in 20 minutes!"
+printMessage<10>();  // Prints "Learn C++ faster in only 10 minutes!"
+
+
 /////////////////////
 // Exception Handling
 /////////////////////
@@ -441,12 +519,13 @@ int main () {
 // (see http://en.cppreference.com/w/cpp/error/exception)
 // but any type can be thrown an as exception
 #include <exception>
+#include <stdexcept>
 
 // All exceptions thrown inside the _try_ block can be caught by subsequent
 // _catch_ handlers.
 try {
     // Do not allocate exceptions on the heap using _new_.
-    throw std::exception("A problem occurred");
+    throw std::runtime_error("A problem occurred");
 }
 // Catch exceptions by const reference if they are objects
 catch (const std::exception& ex)
@@ -537,7 +616,7 @@ void doSomethingWithAFile(const char* filename)
 {
     FILE* fh = fopen(filename, "r"); // Open the file in read mode
     if (fh == nullptr)
-        throw std::exception("Could not open the file.");
+        throw std::runtime_error("Could not open the file.");
 
     try {
         doSomethingWithTheFile(fh);
@@ -586,8 +665,56 @@ void doSomethingWithAFile(const std::string& filename)
 //   vector (i.e. self-resizing array), hash maps, and so on
 //   all automatically destroy their contents when they fall out of scope.
 // - Mutexes using lock_guard and unique_lock
+
+
+/////////////////////
+// Fun stuff
+/////////////////////
+
+// Aspects of C++ that may be surprising to newcomers (and even some veterans).
+// This section is, unfortunately, wildly incomplete; C++ is one of the easiest
+// languages with which to shoot yourself in the foot.
+
+// You can override private methods!
+class Foo {
+  virtual void bar();
+};
+class FooSub : public Foo {
+  virtual void bar();  // overrides Foo::bar!
+};
+
+
+// 0 == false == NULL (most of the time)!
+bool* pt = new bool;
+*pt = 0;  // Sets the value points by 'pt' to false.
+pt = 0;  // Sets 'pt' to the null pointer. Both lines compile without warnings.
+
+// nullptr is supposed to fix some of that issue:
+int* pt2 = new int;
+*pt2 = nullptr;  // Doesn't compile
+pt2 = nullptr;  // Sets pt2 to null.
+
+// But somehow 'bool' type is an exception (this is to make `if (ptr)` compile).
+*pt = nullptr;  // This still compiles, even though '*pt' is a bool!
+
+
+// '=' != '=' != '='!
+// Calls Foo::Foo(const Foo&) or some variant copy constructor.
+Foo f2;
+Foo f1 = f2;
+
+// Calls Foo::Foo(const Foo&) or variant, but only copies the 'Foo' part of
+// 'fooSub'. Any extra members of 'fooSub' are discarded. This sometimes
+// horrifying behavior is called "object slicing."
+FooSub fooSub;
+Foo f1 = fooSub;
+
+// Calls Foo::operator=(Foo&) or variant.
+Foo f1;
+f1 = f2;
+
 ```
-Futher Reading:
+Further Reading:
 
 An up-to-date language reference can be found at
 <http://cppreference.com/w/cpp>

clojure.html.markdown

@@ -22,7 +22,7 @@ and often automatically.
 ; Clojure is written in "forms", which are just
 ; lists of things inside parentheses, separated by whitespace.
 ;
-; The clojure reader  assumes that the first thing is a
+; The clojure reader assumes that the first thing is a
 ; function or macro to call, and the rest are arguments.
 
 ; The first call in a file should be ns, to set the namespace

compojure.html.markdown

@@ -155,8 +155,8 @@ Now, your handlers may utilize query parameters:
 ```clojure
 (defroutes myapp
   (GET "/posts" req
-    (let [title (get (:params req) "title")
+    (let [title (get (:params req) :title)
-          author (get (:params req) "author")]
+          author (get (:params req) :author)]
       (str "Title: " title ", Author: " author))))
 ```
 
@@ -165,8 +165,8 @@ Or, for POST and PUT requests, form parameters as well
 ```clojure
 (defroutes myapp
   (POST "/posts" req
-    (let [title (get (:params req) "title")
+    (let [title (get (:params req) :title)
-          author (get (:params req) "author")]
+          author (get (:params req) :author)]
       (str "Title: " title ", Author: " author))))
 ```
 

elisp.html.markdown

@@ -305,7 +305,7 @@ filename: learn-emacs-lisp.el
 (defun boldify-names ()
     (switch-to-buffer-other-window "*test*")
     (goto-char (point-min))
-    (while (re-search-forward "Bonjour \\([^!]+\\)!" nil 't)
+    (while (re-search-forward "Bonjour \\(.+\\)!" nil 't)
       (add-text-properties (match-beginning 1)
                            (match-end 1)
                            (list 'face 'bold)))
@@ -318,7 +318,7 @@ filename: learn-emacs-lisp.el
 ;; The regular expression is "Bonjour \\(.+\\)!" and it reads:
 ;; the string "Bonjour ", and
 ;; a group of            | this is the \\( ... \\) construct
-;;   any character not ! | this is the [^!]
+;;   any character       | this is the .
 ;;   possibly repeated   | this is the +
 ;; and the "!" string.
 

elixir.html.markdown

@@ -195,7 +195,7 @@ cond do
     "But I will"
 end
 
-# It is common to see the last condition equal to `true`, which will always match.
+# It is common to set the last condition equal to `true`, which will always match.
 cond do
   1 + 1 == 3 ->
     "I will never be seen"

erlang.html.markdown

@@ -18,7 +18,7 @@ filename: learnerlang.erl
 % Periods (`.`) (followed by whitespace) separate entire functions and
 % expressions in the shell.
 % Semicolons (`;`) separate clauses. We find clauses in several contexts:
-% function definitions and in `case`, `if`, `try..catch` and `receive`
+% function definitions and in `case`, `if`, `try..catch`, and `receive`
 % expressions.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -27,20 +27,20 @@ filename: learnerlang.erl
 
 Num = 42.  % All variable names must start with an uppercase letter.
 
-% Erlang has single assignment variables, if you try to assign a different value
+% Erlang has single-assignment variables; if you try to assign a different
-% to the variable `Num`, you’ll get an error.
+% value to the variable `Num`, you’ll get an error.
 Num = 43. % ** exception error: no match of right hand side value 43
 
 % In most languages, `=` denotes an assignment statement. In Erlang, however,
-% `=` denotes a pattern matching operation. `Lhs = Rhs` really means this:
+% `=` denotes a pattern-matching operation. `Lhs = Rhs` really means this:
-% evaluate the right side (Rhs), and then match the result against the pattern
+% evaluate the right side (`Rhs`), and then match the result against the
-% on the left side (Lhs).
+% pattern on the left side (`Lhs`).
 Num = 7 * 6.
 
-% Floating point number.
+% Floating-point number.
 Pi = 3.14159.
 
-% Atoms, are used to represent different non-numerical constant values. Atoms
+% Atoms are used to represent different non-numerical constant values. Atoms
 % start with lowercase letters, followed by a sequence of alphanumeric
 % characters or the underscore (`_`) or at (`@`) sign.
 Hello = hello.
@@ -53,34 +53,34 @@ AtomWithSpace = 'some atom with space'.
 % Tuples are similar to structs in C.
 Point = {point, 10, 45}.
 
-% If we want to extract some values from a tuple, we use the pattern matching
+% If we want to extract some values from a tuple, we use the pattern-matching
 % operator `=`.
 {point, X, Y} = Point.  % X = 10, Y = 45
 
 % We can use `_` as a placeholder for variables that we’re not interested in.
 % The symbol `_` is called an anonymous variable. Unlike regular variables,
-% several occurrences of _ in the same pattern don’t have to bind to the same
+% several occurrences of `_` in the same pattern don’t have to bind to the
-% value.
+% same value.
 Person = {person, {name, {first, joe}, {last, armstrong}}, {footsize, 42}}.
 {_, {_, {_, Who}, _}, _} = Person.  % Who = joe
 
 % We create a list by enclosing the list elements in square brackets and
 % separating them with commas.
 % The individual elements of a list can be of any type.
-% The first element of a list is the head of the list. If you imagine removing the
+% The first element of a list is the head of the list. If you imagine removing
-% head from the list, what’s left is called the tail of the list.
+% the head from the list, what’s left is called the tail of the list.
 ThingsToBuy = [{apples, 10}, {pears, 6}, {milk, 3}].
 
 % If `T` is a list, then `[H|T]` is also a list, with head `H` and tail `T`.
 % The vertical bar (`|`) separates the head of a list from its tail.
 % `[]` is the empty list.
-% We can extract elements from a list with a pattern matching operation. If we
+% We can extract elements from a list with a pattern-matching operation. If we
 % have a nonempty list `L`, then the expression `[X|Y] = L`, where `X` and `Y`
 % are unbound variables, will extract the head of the list into `X` and the tail
 % of the list into `Y`.
 [FirstThing|OtherThingsToBuy] = ThingsToBuy.
 % FirstThing = {apples, 10}
-% OtherThingsToBuy = {pears, 6}, {milk, 3}
+% OtherThingsToBuy = [{pears, 6}, {milk, 3}]
 
 % There are no strings in Erlang. Strings are really just lists of integers.
 % Strings are enclosed in double quotation marks (`"`).
@@ -117,17 +117,19 @@ c(geometry).  % {ok,geometry}
 geometry:area({rectangle, 10, 5}).  % 50
 geometry:area({circle, 1.4}).  % 6.15752
 
-% In Erlang, two functions with the same name and different arity (number of arguments)
+% In Erlang, two functions with the same name and different arity (number of
-% in the same module represent entirely different functions.
+% arguments) in the same module represent entirely different functions.
 -module(lib_misc).
--export([sum/1]). % export function `sum` of arity 1 accepting one argument: list of integers.
+-export([sum/1]). % export function `sum` of arity 1
+                  % accepting one argument: list of integers.
 sum(L) -> sum(L, 0).
 sum([], N)    -> N;
 sum([H|T], N) -> sum(T, H+N).
 
-% Funs are "anonymous" functions. They are called this way because they have no
+% Funs are "anonymous" functions. They are called this way because they have
-% name. However they can be assigned to variables.
+% no name. However, they can be assigned to variables.
-Double = fun(X) -> 2*X end. % `Double` points to an anonymous function with handle: #Fun<erl_eval.6.17052888>
+Double = fun(X) -> 2 * X end. % `Double` points to an anonymous function
+                              % with handle: #Fun<erl_eval.6.17052888>
 Double(2).  % 4
 
 % Functions accept funs as their arguments and can return funs.
@@ -140,8 +142,9 @@ Triple(5).  % 15
 % The notation `[F(X) || X <- L]` means "the list of `F(X)` where `X` is taken
 % from the list `L`."
 L = [1,2,3,4,5].
-[2*X || X <- L].  % [2,4,6,8,10]
+[2 * X || X <- L].  % [2,4,6,8,10]
-% A list comprehension can have generators and filters which select subset of the generated values.
+% A list comprehension can have generators and filters, which select subset of
+% the generated values.
 EvenNumbers = [N || N <- [1, 2, 3, 4], N rem 2 == 0]. % [2, 4]
 
 % Guards are constructs that we can use to increase the power of pattern
@@ -155,17 +158,31 @@ max(X, Y) -> Y.
 
 % A guard is a series of guard expressions, separated by commas (`,`).
 % The guard `GuardExpr1, GuardExpr2, ..., GuardExprN` is true if all the guard
-% expressions `GuardExpr1, GuardExpr2, ...` evaluate to true.
+% expressions `GuardExpr1`, `GuardExpr2`, ..., `GuardExprN` evaluate to `true`.
 is_cat(A) when is_atom(A), A =:= cat -> true;
 is_cat(A) -> false.
 is_dog(A) when is_atom(A), A =:= dog -> true;
 is_dog(A) -> false.
 
-% A `guard sequence` is either a single guard or a series of guards, separated
+% We won't dwell on the `=:=` operator here; just be aware that it is used to
-%by semicolons (`;`). The guard sequence `G1; G2; ...; Gn` is true if at least
+% check whether two Erlang expressions have the same value *and* the same type.
-% one of the guards `G1, G2, ...` evaluates to true.
+% Contrast this behaviour to that of the `==` operator:
-is_pet(A) when is_dog(A); is_cat(A) -> true;
+1 + 2 =:= 3.   % true
-is_pet(A) -> false.
+1 + 2 =:= 3.0. % false
+1 + 2 ==  3.0. % true
+
+% A guard sequence is either a single guard or a series of guards, separated
+% by semicolons (`;`). The guard sequence `G1; G2; ...; Gn` is true if at
+% least one of the guards `G1`, `G2`, ..., `Gn` evaluates to `true`.
+is_pet(A) when is_atom(A), (A =:= dog) or (A =:= cat) -> true;
+is_pet(A)                                             -> false.
+
+% Warning: not all valid Erlang expressions can be used as guard expressions;
+% in particular, our `is_cat` and `is_dog` functions cannot be used within the
+% guard sequence in `is_pet`'s definition. For a description of the
+% expressions allowed in guard sequences, refer to this
+% [section](http://erlang.org/doc/reference_manual/expressions.html#id81912)
+% of the Erlang reference manual.
 
 % Records provide a method for associating a name with a particular element in a
 % tuple.
@@ -188,7 +205,7 @@ X = #todo{}.
 X1 = #todo{status = urgent, text = "Fix errata in book"}.
 % #todo{status = urgent, who = joe, text = "Fix errata in book"}
 X2 = X1#todo{status = done}.
-% #todo{status = done,who = joe,text = "Fix errata in book"}
+% #todo{status = done, who = joe, text = "Fix errata in book"}
 
 % `case` expressions.
 % `filter` returns a list of all elements `X` in a list `L` for which `P(X)` is
@@ -209,8 +226,8 @@ max(X, Y) ->
     true -> nil
   end.
 
-% Warning: at least one of the guards in the `if` expression must evaluate to true;
+% Warning: at least one of the guards in the `if` expression must evaluate to
-% otherwise, an exception will be raised.
+% `true`; otherwise, an exception will be raised.
 
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -218,7 +235,7 @@ max(X, Y) ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 % Exceptions are raised by the system when internal errors are encountered or
-% explicitly in code by calling `throw(Exception)`, `exit(Exception)` or
+% explicitly in code by calling `throw(Exception)`, `exit(Exception)`, or
 % `erlang:error(Exception)`.
 generate_exception(1) -> a;
 generate_exception(2) -> throw(a);
@@ -227,7 +244,7 @@ generate_exception(4) -> {'EXIT', a};
 generate_exception(5) -> erlang:error(a).
 
 % Erlang has two methods of catching an exception. One is to enclose the call to
-% the function, which raised the exception within a `try...catch` expression.
+% the function that raises the exception within a `try...catch` expression.
 catcher(N) ->
   try generate_exception(N) of
     Val -> {N, normal, Val}
@@ -241,23 +258,24 @@ catcher(N) ->
 % exception, it is converted into a tuple that describes the error.
 catcher(N) -> catch generate_exception(N).
 
-
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% 4. Concurrency
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 % Erlang relies on the actor model for concurrency. All we need to write
-% concurrent programs in erlang are three primitives: spawning processes,
+% concurrent programs in Erlang are three primitives: spawning processes,
 % sending messages and receiving messages.
 
-% To start a new process we use the `spawn` function, which takes a function
+% To start a new process, we use the `spawn` function, which takes a function
 % as argument.
 
 F = fun() -> 2 + 2 end. % #Fun<erl_eval.20.67289768>
 spawn(F). % <0.44.0>
 
-% `spawn` returns a pid (process identifier), you can use this pid to send
+% `spawn` returns a pid (process identifier); you can use this pid to send
-% messages to the process. To do message passing we use the `!` operator.
+% messages to the process. To do message passing, we use the `!` operator.
-% For all of this to be useful we need to be able to receive messages. This is
+% For all of this to be useful, we need to be able to receive messages. This is
 % achieved with the `receive` mechanism:
 
 -module(calculateGeometry).
@@ -272,12 +290,13 @@ calculateArea() ->
         io:format("We can only calculate area of rectangles or circles.")
     end.
     
-% Compile the module and create a process that evaluates `calculateArea` in the shell
+% Compile the module and create a process that evaluates `calculateArea` in the
+% shell.
 c(calculateGeometry).
 CalculateArea = spawn(calculateGeometry, calculateArea, []).
 CalculateArea ! {circle, 2}. % 12.56000000000000049738
 
-% The shell is also a process, you can use `self` to get the current pid
+% The shell is also a process; you can use `self` to get the current pid.
 self(). % <0.41.0>
 
 ```

fr-fr/erlang-fr.html.markdown

@@ -0,0 +1,327 @@
+---
+language: erlang
+contributors:
+    - ["Giovanni Cappellotto", "http://www.focustheweb.com/"]
+translators:
+    - ["Julien Cretel", "https://github.com/Jubobs"]
+filename: learnerlang-fr.erl
+lang: fr-fr
+---
+
+```erlang
+% Un signe pour cent marque le début d'un commentaire de fin de ligne.
+
+%% Deux signes pour cent sont utilisés pour commenter les fonctions.
+
+%%% Trois signes pour cent sont utilisés pour commenter les modules.
+
+% Trois symboles de ponctuation sont utilisés en Erlang.
+% Les virgules (`,`) servent à séparer les paramètres dans les appels de
+% fonctions, les contructeurs, et les motifs.
+% Les points (`.`) (suivis par des blancs) servent à séparer les fonctions et
+% les expressions dans l'interpréteur.
+% Les points-virgules (`;`) servent à séparer les clauses. Ces dernières
+% apparaissent dans différent cas de figure : définitions de fonctions et
+% expressions `case`, `if`, `try..catch`, `receive`.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% 1. Variables et filtrage par motif
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+(L'équivalent anglais de *filtrage par motif* est *pattern patching*.)
+
+Nb = 42.  % Chaque nom de variable doit commencer par une lettre majuscule.
+
+% Les variables Erlang ne peuvent être affectées qu'une seule fois ; si vous
+% essayez d'affecter une autre valeur à la variable `Nb`, vous obtiendrez
+% une erreur.
+Nb = 43. % ** exception error: no match of right hand side value 43
+
+% Dans la plupart des languages, `=` indique une affectation. En Erlang,
+% cependant, `=` indique un filtrage par motif. En fait, `Gauche = Droit`
+% signifie ce qui suit : évalue le côté droit (`Droit`), et ensuite filtre le
+% résultat à l'aide du motif du côté gauche (`Gauche`).
+Nb = 7 * 6.
+
+% Nombre en virgule flottante.
+Pi = 3.14159.
+
+% Les atomes représentent des valeurs constantes non-numériques. Un atome
+% commence par une lettre minuscule, suivie d'une séquence composée de
+% caractères alphanumériques, de tirets bas (`_`), ou d'arobases (`@`).
+Bonjour = bonjour.
+AutreNoeud = exemple@noeud.
+
+% Les atomes de valeur autre qu'alphanumérique peuvent être délimités par
+% des guillemets droits simples.
+AtomeAvecEspace = 'un atome contenant des espaces'.
+
+% Les tuples sont similaires aux enregistrements du language C.
+Point = {point, 10, 45}.
+
+% Pour extraire des valeurs d'un tuple, on filtre par motif avec
+% l'opérateur `=`.
+{point, X, Y} = Point.  % X = 10, Y = 45
+
+% On peut utiliser `_` comme caractère joker pour les variables qui ne nous
+% intéressent pas. Le symbol `_` est appelé variable muette. Contrairement
+% aux variables normales, de multiples apparitions de `_` dans un même motif
+% ne lient pas nécessairement à la même valeur.
+Personne = {personne, {nom, {prenom, joe}, {famille, armstrong}},
+                      {pointure, 42}}.
+{_, {_, {_, Qui}, _}, _} = Personne.  % Qui = joe
+
+% Pour créer une liste, on écrit les éléments de la liste entre crochets, en
+% les séparant par des virgules.
+% Les éléments d'une liste peuvent avoir n'importe quel type.
+% Le premier élément d'une liste est appelé la tête de la liste. Si on retire
+% la tête d'une liste, ce qui reste est appelée la queue de la liste.
+Articles = [{pommes, 10}, {poires, 6}, {lait, 3}].
+
+% Si `Q` est une liste, alors `[T|Q]` est aussi une liste dont la tête est `T`
+% et dont la queue est `Q`. La barre verticale (`|`) sépare la tête d'une
+% liste de sa queue.
+% `[]` est la liste vide.
+% On peut extraire des éléments d'une liste par filtrage de motif. Si `L` est
+% une liste non vide, alors l'expression `[X|Y] = L`, où `X` et `Y` sont des
+% variables non affectées, va extraire la tête de la liste dans `X` et la
+% queue de la liste dans `Y`.
+[PremierArticle|AutresArticles] = Articles.
+% PremierArticle = {pommmes, 10}
+% AutresArticles = [{poires, 6}, {lait, 3}]
+
+% Il n'y a pas de chaînes de caractères en Erlang. Les chaînes de caractères
+% ne sont rien de plus que des listes d'entiers.
+% Les chaînes de caractères sont délimitées par des guillemets droits doubles
+% (`"`).
+Nom = "Bonjour".
+[66, 111, 110, 106, 111, 117, 114] = "Bonjour".
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% 2. Programmation séquentielle.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+% Les modules constituent l'unité de base d'un programme Erlang. Toutes les
+% fonctions que l'on écrit sont enregistrées dans des modules. Les modules sont
+% enregistrés dans des fichiers avec une extension `.erl`.
+% Les modules doivent être compilés afin d'éxecuter le programme.
+% Un module compilé a une extension `.beam`.
+-module(geometrie).
+-export([aire/1]). % la liste des fonctions exportées par le module.
+
+% La fonction `aire` est composée de deux clauses. Les clauses sont séparées
+% par un point-virgule, et la dernière clause est suivie d'un point et un
+% espace blanc. Chaque clause a une en-tête et un corps ; l'en-tête consiste
+% en un nom de fonction suivi d'un motif (entre parenthèses), et le corps
+% consiste en une séquence d'expressions, qui sont évaluées si le motif de
+% l'en-tête est cohérent par rapport à la valeur des paramètres d'appel.
+% L'expression est filtrée séquentiellement par les différents motifs, dans
+% l'ordre dans lequel ils apparaissent dans la définition de la fonction.
+aire({rectangle, Largeur, Hauteur}) -> Largeur * Hauteur;
+aire({cercle, R})                   -> 3.14159 * R * R.
+
+% Compilation du code du fichier geometrie.erl.
+c(geometrie).  % {ok,geometrie}
+
+% Le nom du module doit être inclus avec le nom de la fonction afin
+% d'identifier précisément quelle fonction on souhaite appeler.
+geometrie:aire({rectangle, 10, 5}).  % 50
+geometrie:area({cercle, 1.4}).  % 6.15752
+
+% En Erlang, deux fonctions portant le même nom mais ayant des arités
+% différentes (c'est à dire ne prenant pas le même nombre de paramètres)
+% au sein d'un même module représentent des fonctions complètement
+% différentes.
+-module(lib_divers).
+-export([somme/1]). % exporte la fonction `somme` d'arité 1
+                    % acceptant un paramètre : une liste d'entiers.
+somme(L) -> somme(L, 0).
+somme([], N)    -> N;
+somme([T|Q], N) -> somme(Q, T+N).
+
+% Les `fun`s sont des fonctions "anonymes" ; elles sont appelées ainsi parce
+% qu'elles n'ont pas de nom. Cependant, elles peuvent être affectées à des
+% variables.
+Doubler = fun(X) -> 2 * X end. % `Doubler` pointe vers une fonction anonyme
+                               % dont le handle est : #Fun<erl_eval.6.17052888>
+Doubler(2).  % 4
+
+% Les fonctions peuvent prendre des `fun`s comme paramètres et peuvent renvoyer
+% des `fun`s.
+Mult = fun(Fois) -> ( fun(X) -> X * Fois end ) end.
+Tripler = Mult(3).
+Tripler(5).  % 15
+
+% Les listes en compréhension sont des expressions qui créent des listes sans
+% requérir ni `fun`s, ni maps, ni filters.
+% La notation `[F(X) || X <- L]` signifie "la liste des `F(X)` où `X` est
+% extrait de la liste `L`."
+L = [1,2,3,4,5].
+[2 * X || X <- L].  % [2,4,6,8,10]
+% Une liste en compréhension peut être constituée de générateurs, ainsi que de
+% gardes, qui sélectionnent un sous-ensemble des valeurs générées.
+NombresPairs = [N || N <- [1, 2, 3, 4], N rem 2 == 0]. % [2, 4]
+
+% La garde est un élément syntaxique qui rend le filtrage par motif encore
+% plus puissant. Les gardes permettent de d'effectuer de simple tests et
+% comparaisons sur les variables d'un motif. Les gardes peuvent être
+% utilisées dans les en-têtes de fonctions, au sein desquelles elles sont
+% introduites par le mot-clé `when`, ou encore à n'importe quel endroit où
+% une expression est autorisée.
+max(X, Y) when X > Y -> X;
+max(X, Y) -> Y.
+
+% Une garde est une série d'expressions gardes, séparées par des virgules (`,`).
+% La garde `ExprGarde1, ExprGarde2, ..., ExprGardeN` est vraie si toutes les
+% expressions gardes `ExprGarde1`, `ExprGarde2, ..., `ExprGardeN` ont pour
+% valeur `true`.
+est_chat(A) when is_atom(A), A =:= chat -> true;
+est_chat(A) -> false.
+est_chien(A) when is_atom(A), A =:= chien -> true;
+est_chien(A) -> false.
+
+% Une séquence de gardes est composée soit d'une seule garde ou bien d'une
+% série de gardes, séparées par des points-virgules (`;`). La séquence de
+% gardes `G1; G2; ...; Gn` est vraie si au moins l'une des gardes `G1`, `G2`,
+% ..., `Gn` a pour valeur `true`.
+est_animal(A) when is_atom(A), (A =:= chien) or (A =:= chat) -> true;
+est_animal(A)                                                -> false.
+
+% Attention : toutes les expressions Erlang valides ne peuvent pas être
+% utilisées comme expressions gardes ; en particulier, nos fonctions
+% `est_chat` et `est_chien` ne sont pas autorisées au sein de la séquence de
+% gardes dans la définition de `est_animal`. Pour plus de détails sur les
+% expressions autorisées ands les séquences de gardes, voir cette
+% [section](http://erlang.org/doc/reference_manual/expressions.html#id81912)
+% du manuel Erlang.
+
+% Les enregistrements permettent d'associer un nom à un certain élément dans
+% un tuple.
+% Les enregistrements peuvent être définis dans des fichiers sources Erlang
+% ou bien dans des fichiers avec une extension `.hrl`, qui sont ensuite inclus
+% dans des fichiers sources Erlang.
+-record(afaire, {
+  statut = rappel,  % Valeur par défaut
+  qui = joe,
+  texte
+}).
+
+% Les définitions d'enregistrements doivent être lues dans l'interpreteur
+% pour qu'on puisse définir un enregistrement. On utilise la fonction `rr`
+% (abbréviation de *read records* en anglais, ou *lire enregistrements* en
+% français) pour ça.
+rr("enregistrements.hrl").  % [afaire]
+
+% Création et mise à jour d'enregistrements :
+X = #afaire{}.
+% #afaire{statut = rappel, qui = joe, texte = undefined}
+X1 = #afaire{statut = urgent, texte = "Corriger erreurs dans livre"}.
+% #afaire{statut = urgent, qui = joe, texte = "Corriger erreurs dans livre"}
+X2 = X1#afaire{statut = fini}.
+% #afaire{statut = fini, qui = joe, texte = "Corriger erreurs dans livre"}
+
+% Expressions `case`.
+% `filter` renvoie une liste de tous les éléments `X` d'une liste `L` pour
+% lesquels `P(X)` est vrai.
+filter(P, [H|T]) ->
+  case P(H) of
+    true -> [H|filter(P, T)];
+    false -> filter(P, T)
+  end;
+filter(P, []) -> [].
+filter(fun(X) -> X rem 2 == 0 end, [1, 2, 3, 4]). % [2, 4]
+
+% Expressions `if`.
+max(X, Y) ->
+  if
+    X > Y -> X;
+    X < Y -> Y;
+    true -> nil
+  end.
+
+% Attention : au moins l'une des gardes dans l'expression `if` doit avoir pour
+% valeur `true` ; autrement, une exception sera lancée.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% 3. Exceptions.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+% Des exceptions sont lancées par le système quand des erreurs internes
+% surviennent, ou de manière explicite dans le programme en appelant
+% `throw(Exception)`, `exit(Exception)`, ou `erlang:error(Exception)`.
+generer_exception(1) -> a;
+generer_exception(2) -> throw(a);
+generer_exception(3) -> exit(a);
+generer_exception(4) -> {'EXIT', a};
+generer_exception(5) -> erlang:error(a).
+
+% Erlang dispose de deux méthodes pour capturer une exception. La première
+% consiste à inclure l'appel de de la fonction qui lance l'exception dans une
+% expression `try...catch`.
+catcher(N) ->
+  try generer_exception(N) of
+    Val -> {N, normal, Val}
+  catch
+    throw:X -> {N, caught, thrown, X};
+    exit:X -> {N, caught, exited, X};
+    error:X -> {N, caught, error, X}
+  end.
+
+% L'autre méthode consiste à inclure l'appel dans une expression `catch`.
+% Quand une exception est capturée, elle est convertie en un tuple qui décrit
+% l'erreur.
+catcher(N) -> catch generer_exception(N).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% 4. Concurrence
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+% Erlang est basé sur le modèle d'acteur pour la concurrence. Seulement trois
+% opérations sont requises pour écrire des programmes concurrents en Erlang :
+% la création de processus, l'envoi de messages, et la réception de messages.
+
+% Pour démarrer un nouveau processus, on utilise la fonction `spawn`, qui
+% prend une fonction comme paramètre.
+
+F = fun() -> 2 + 2 end. % #Fun<erl_eval.20.67289768>
+spawn(F). % <0.44.0>
+
+% `spawn` renvoie un pid (*process identifier* en anglais, ou *identifiant de
+% processus* en français), qui peut être utilisé pour envoyer des messages au
+% processus en question. Pour passer des messages, on utilise l'opérateur `!`.
+% Pour que cela soit utile, on doit aussi être en mesure de recevoir des
+% messages, ce qui est accompli grâce à une clause `receive` :
+
+-module(calculerGeometrie).
+-compile(export_all).
+calculerAire() ->
+    receive
+      {rectangle, W, H} ->
+        W * H;
+      {cercle, R} ->
+        3.14 * R * R;
+      _ ->
+        io:format("Seule l'aire d'un rectangle / cercle peut etre calculee.")
+    end.
+
+% Compilation du module and création d'un processus qui évalue `calculerAire`
+% dans l'interpréteur.
+c(calculerGeometrie).
+CalculerAire = spawn(calculerGeometrie, calculerAire, []).
+CalculerAire ! {cercle, 2}. % 12.56000000000000049738
+
+% L'interpréteur est lui-même un processus ; on peut utiliser `self` pour
+% obtenir le pid actuel.
+self(). % <0.41.0>
+
+```
+
+## Ressources (en anglais)
+
+* ["Learn You Some Erlang for great good!"](http://learnyousomeerlang.com/)
+* ["Programming Erlang: Software for a Concurrent World" by Joe Armstrong](http://pragprog.com/book/jaerlang/programming-erlang)
+* [Erlang/OTP Reference Documentation](http://www.erlang.org/doc/)
+* [Erlang - Programming Rules and Conventions](http://www.erlang.se/doc/programming_rules.shtml)

fr-fr/json-fr.html.markdown

@@ -0,0 +1,62 @@
+---
+language: json
+filename: learnjson-fr.json
+contributors:
+  - ["Anna Harren", "https://github.com/iirelu"]
+  - ["Marco Scannadinari", "https://github.com/marcoms"]
+translators:
+  - ["Alois de Gouvello","https://github.com/aloisdg"]
+lang: fr-fr
+---
+
+Comme JSON est un format d'échange de données extrêmement simple, ce Apprendre X en Y minutes
+est susceptible d'être le plus simple jamais réalisé.
+
+JSON dans son état le plus pur n'a aucun commentaire, mais la majorité des parseurs accepterons
+les commentaires du langage C (`//`, `/* */`). Pour les besoins de ce document, cependant,
+tout sera du JSON 100% valide. Heureusement, il s'explique par lui-même.
+
+
+```json
+{
+  "Clé": "valeur",
+  
+  "Clés": "devront toujours être entourées par des guillemets",
+  "nombres": 0,
+  "chaînes de caractères": "Hellø, wørld. Tous les caractères Unicode sont autorisés, accompagné d'un \"caractère d'échappement\".",
+  "a des booléens ?": true,
+  "rien": null,
+
+  "grand nombre": 1.2e+100,
+
+  "objets": {
+    "commentaire": "La majorité de votre strucutre sera des objets.",
+
+    "tableau": [0, 1, 2, 3, "Les tableaux peuvent contenir n'importe quoi.", 5],
+
+    "un autre objet": {
+      "commentaire": "Ces choses peuvent être imbriquées. C'est très utile."
+    }
+  },
+
+  "bêtises": [
+    {
+      "sources de potassium": ["bananes"]
+    },
+    [
+      [1, 0, 0, 0],
+      [0, 1, 0, 0],
+      [0, 0, 1, "neo"],
+      [0, 0, 0, 1]
+    ]
+  ],
+  
+  "style alternatif": {
+    "commentaire": "regarde ça !"
+  , "position de la virgule": "n'a pas d'importance - aussi longtemps qu'elle est avant la valeur, alors elle est valide."
+  , "un autre commentaire": "comme c'est gentil"
+  },
+
+  "C'était court": "Et, vous avez terminé. Maintenant, vous savez tout ce que JSON a à offrir."
+}
+```

fr-fr/r-fr.html.markdown

@@ -0,0 +1,747 @@
+---
+language: R
+contributors:
+    - ["e99n09", "http://github.com/e99n09"]
+    - ["isomorphismes", "http://twitter.com/isomorphisms"]
+translators:
+    - ["Anne-Catherine Dehier", "https://github.com/spellart"]
+filename: learnr-fr.r
+lang: fr-fr
+---
+
+R est un langage de programmation statistique. Il dispose de nombreuses
+bibliothèques pour le téléchargement et le nettoyage d'ensembles de données,
+l'exécution de procédures statistiques, et la réalisation de graphiques.
+On peut également exécuter des commmandes `R` au sein d'un document LaTeX.
+
+
+```r
+
+# Les commentaires commencent avec des symboles numériques.
+
+# Il n'est pas possible de faire des commentaires multilignes,
+# mais on peut placer plusieurs commentaires les uns en dessous
+# des autres comme ceci.
+
+# Sur Mac, taper COMMAND-ENTER pour exécuter une ligne
+# et sur Windows taper CTRL-ENTER
+
+
+
+########################################################################
+# Les choses que vous pouvez faire sans rien comprendre
+# à la programmation
+########################################################################
+
+# Dans cette section, nous vous montrons quelques trucs cools que vous
+# pouvez faire avec R sans rien comprendre à la programmation.
+# Ne vous inquiétez pas si vous ne comprenez pas tout ce que le code fait.
+# Profitez simplement !
+
+data()          # parcours les ensembles de données préchargées
+data(rivers)	# récupère ceci : "Lengths of Major North American Rivers"
+ls()            # notez que "rivers" apparaît maintenant dans votre espace de travail
+head(rivers)	# donne un aperçu des données
+# 735 320 325 392 524 450
+
+length(rivers)	# Combien de rivers ont été mesurées ?
+# 141
+summary(rivers) # Quelles sont les principales données statistiques ?
+#   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
+#  135.0   310.0   425.0   591.2   680.0  3710.0
+
+# Fait un diagramme à tiges et à feuilles (visualisation de données de
+# types histogramme)
+stem(rivers)
+
+
+#  Le point décimal est de 2 chiffres à droite du |
+#
+#   0 | 4
+#   2 | 011223334555566667778888899900001111223333344455555666688888999
+#   4 | 111222333445566779001233344567
+#   6 | 000112233578012234468
+#   8 | 045790018
+#  10 | 04507
+#  12 | 1471
+#  14 | 56
+#  16 | 7
+#  18 | 9
+#  20 |
+#  22 | 25
+#  24 | 3
+#  26 |
+#  28 |
+#  30 |
+#  32 |
+#  34 |
+#  36 | 1
+
+stem(log(rivers)) # Notez que les données ne sont ni normales
+# ni lognormales !
+# Prenez-ça, la courbe en cloche
+
+#  Le point décimal est à 1 chiffre à gauche du |
+#
+#  48 | 1
+#  50 |
+#  52 | 15578
+#  54 | 44571222466689
+#  56 | 023334677000124455789
+#  58 | 00122366666999933445777
+#  60 | 122445567800133459
+#  62 | 112666799035
+#  64 | 00011334581257889
+#  66 | 003683579
+#  68 | 0019156
+#  70 | 079357
+#  72 | 89
+#  74 | 84
+#  76 | 56
+#  78 | 4
+#  80 |
+#  82 | 2
+
+# Fait un histogramme :
+hist(rivers, col="#333333", border="white", breaks=25) # amusez-vous avec ces paramètres
+hist(log(rivers), col="#333333", border="white", breaks=25) # vous ferez plus de tracés plus tard
+
+# Ici d'autres données qui viennent préchargées. R en a des tonnes.
+data(discoveries)
+plot(discoveries, col="#333333", lwd=3, xlab="Year",
+     main="Number of important discoveries per year")
+plot(discoveries, col="#333333", lwd=3, type = "h", xlab="Year",
+     main="Number of important discoveries per year")
+
+# Plutôt que de laisser l'ordre par défaut (par année)
+# Nous pourrions aussi trier pour voir ce qu'il y a de typique
+sort(discoveries)
+#  [1]  0  0  0  0  0  0  0  0  0  1  1  1  1  1  1  1  1  1  1  1  1  2  2  2  2
+# [26]  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  2  3  3  3
+# [51]  3  3  3  3  3  3  3  3  3  3  3  3  3  3  3  3  3  4  4  4  4  4  4  4  4
+# [76]  4  4  4  4  5  5  5  5  5  5  5  6  6  6  6  6  6  7  7  7  7  8  9 10 12
+
+stem(discoveries, scale=2)
+#
+#  Le point décimale est à la |
+#
+#   0 | 000000000
+#   1 | 000000000000
+#   2 | 00000000000000000000000000
+#   3 | 00000000000000000000
+#   4 | 000000000000
+#   5 | 0000000
+#   6 | 000000
+#   7 | 0000
+#   8 | 0
+#   9 | 0
+#  10 | 0
+#  11 |
+#  12 | 0
+
+max(discoveries)
+# 12
+summary(discoveries)
+#   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
+#    0.0     2.0     3.0     3.1     4.0    12.0
+
+# Lance un dé plusieurs fois
+round(runif(7, min=.5, max=6.5))
+# 1 4 6 1 4 6 4
+# Vos numéros diffèreront des miens à moins que nous mettions
+# le même random.seed(31337)
+
+# Dessine à partir d'une normale Gaussienne 9 fois
+rnorm(9)
+# [1]  0.07528471  1.03499859  1.34809556 -0.82356087  0.61638975 -1.88757271
+# [7] -0.59975593  0.57629164  1.08455362
+
+
+
+##############################################################
+# les types de données et l'arithmétique de base
+##############################################################
+
+# Maintenant pour la partie orientée programmation du tutoriel.
+# Dans cette section vous rencontrerez les types de données importants de R :
+# les entiers, les numériques, les caractères, les logiques, et les facteurs.
+
+# LES ENTIERS
+# Les entiers de type long sont écrits avec L
+5L # 5
+class(5L) # "integer"
+# (Essayez ?class pour plus d'informations sur la fonction class().)
+# Avec R, chaque valeur seule, comme 5L, est considérée comme
+# un vecteur de longueur 1
+length(5L) # 1
+# On peut avoir un vecteur d'entiers avec une longueur > 1 :
+c(4L, 5L, 8L, 3L) # 4 5 8 3
+length(c(4L, 5L, 8L, 3L)) # 4
+class(c(4L, 5L, 8L, 3L)) # "integer"
+
+# LES NUMÉRIQUES
+# Un "numeric" est un nombre à virgule flottante d'une précision double
+5 # 5
+class(5) # "numeric"
+# Encore une fois, tout dans R est un vecteur ;
+# Vous pouvez faire un vecteur numérique avec plus d'un élément
+c(3,3,3,2,2,1) # 3 3 3 2 2 1
+# Vous pouvez aussi utiliser la notation scientifique
+5e4 # 50000
+6.02e23 # nombre d'Avogadro
+1.6e-35 # longueur de Planck
+# Vous pouvez également avoir des nombres infiniments grands ou petits
+class(Inf)	# "numeric"
+class(-Inf)	# "numeric"
+# Vous pouvez utiliser "Inf", par exemple, dans integrate(dnorm, 3, Inf);
+# Ça permet d'éviter de réaliser une table de la loi normale.
+
+# ARITHMÉTIQUES DE BASE
+# Vous pouvez faire de l'arithmétique avec des nombres
+# Faire des opérations arithmétiques en mixant des entiers
+# et des numériques
+# donne un autre numérique
+10L + 66L # 76      # un entier plus un entier donne un entier
+53.2 - 4  # 49.2    # un numérique moins un numérique donne un numérique
+2.0 * 2L  # 4       # un numérique multiplié par un entier donne un numérique
+3L / 4    # 0.75    # un entier sur un numérique donne un numérique
+3 %% 2    # 1       # le reste de deux numériques est un autre numérique
+# Les opérations arithmétiques illégales donnent un "Not A Number" :
+0 / 0 # NaN
+class(NaN) # "numeric"
+# Vous pouvez faire des opérations arithmétiques avec deux vecteurs d'une
+# longueur plus grande que 1, à condition que la longueur du plus grand
+# vecteur soit un multiple entier du plus petit
+c(1,2,3) + c(1,2,3) # 2 4 6
+
+# LES CARACTÈRES
+# Il n'y a pas de différences entre les chaînes de caractères et
+# les caractères en R
+"Horatio" # "Horatio"
+class("Horatio") # "character"
+class('H') # "character"
+# Ceux-ci sont tous les deux des vecteurs de longueur 1
+# Ici un plus long :
+c('alef', 'bet', 'gimmel', 'dalet', 'he')
+# =>
+# "alef"   "bet"    "gimmel" "dalet"  "he"
+length(c("Call","me","Ishmael")) # 3
+# Vous pouvez utiliser des expressions rationnelles sur les vecteurs de caractères :
+substr("Fortuna multis dat nimis, nulli satis.", 9, 15) # "multis "
+gsub('u', 'ø', "Fortuna multis dat nimis, nulli satis.") # "Fortøna møltis dat nimis, nølli satis."
+# R possède plusieurs vecteurs de caractères préconstruits :
+letters
+# =>
+#  [1] "a" "b" "c" "d" "e" "f" "g" "h" "i" "j" "k" "l" "m" "n" "o" "p" "q" "r" "s"
+# [20] "t" "u" "v" "w" "x" "y" "z"
+month.abb # "Jan" "Feb" "Mar" "Apr" "May" "Jun" "Jul" "Aug" "Sep" "Oct" "Nov" "Dec"
+
+# LES TYPES BOOLÉENS
+# En R, un "logical" est un booléen
+class(TRUE)	# "logical"
+class(FALSE)	# "logical"
+# Leur comportement est normal
+TRUE == TRUE	# TRUE
+TRUE == FALSE	# FALSE
+FALSE != FALSE	# FALSE
+FALSE != TRUE	# TRUE
+# Les données manquantes (NA) sont logiques également
+class(NA)	# "logical"
+# On utilise | et & pour les operations logiques.
+# OR
+TRUE | FALSE	# TRUE
+# AND
+TRUE & FALSE	# FALSE
+# Vous pouvez tester si x est TRUE
+isTRUE(TRUE)	# TRUE
+# Ici nous avons un vecteur de type logique avec plusieurs éléments :
+c('Z', 'o', 'r', 'r', 'o') == "Zorro" # FALSE FALSE FALSE FALSE FALSE
+c('Z', 'o', 'r', 'r', 'o') == "Z" # TRUE FALSE FALSE FALSE FALSE
+
+# LES FACTEURS
+# Les facteurs sont généralement utilisés pour y stocker des
+# variables qualitatives (catégorielles).
+# Les facteurs peuvent être ordonnés (comme le niveau scolaire
+# des enfants) ou non ordonnés (comme le sexe)
+factor(c("female", "female", "male", NA, "female"))
+#  female female male   <NA>   female
+# Les niveaux : female male
+# Les facteurs possèdent un attribut appelé niveau ("level").
+# Les niveaux sont des vecteurs contenant toutes les valeurs
+# que peuvent prendre les données catégorielles.
+# Notez que les données manquantes n'entrent pas dans le niveau
+levels(factor(c("male", "male", "female", NA, "female"))) # "female" "male"
+# Si le vecteur de facteurs a une longueur 1, ses niveaux seront
+# de longueur 1 également
+length(factor("male")) # 1
+length(levels(factor("male"))) # 1
+# On rencontre communément des facteurs dans des "data frame",
+# un type de données que nous couvrirons plus tard
+data(infert) # "Infertility after Spontaneous and Induced Abortion"
+levels(infert$education) # "0-5yrs"  "6-11yrs" "12+ yrs"
+
+# NULL
+# "NULL" est bizarre ; on l'utilise pour effacer un vecteur
+class(NULL)	# NULL
+parakeet = c("beak", "feathers", "wings", "eyes")
+parakeet
+# =>
+# [1] "beak"     "feathers" "wings"    "eyes"
+parakeet <- NULL
+parakeet
+# =>
+# NULL
+
+# LES CONVERSIONS DE TYPES
+# Les conversions de types servent à forcer une valeur à prendre
+# un type différent
+as.character(c(6, 8)) # "6" "8"
+as.logical(c(1,0,1,1)) # TRUE FALSE  TRUE  TRUE
+# Si vous mettez des éléments de différents types dans un vecteur,
+# des coercitions bizarres se produisent :
+c(TRUE, 4) # 1 4
+c("dog", TRUE, 4) # "dog"  "TRUE" "4"
+as.numeric("Bilbo")
+# =>
+# [1] NA
+# Message d'avertissement :
+# NAs est introduit par coercition
+
+# Notez également : ce n'étaient que des types de données basiques
+# Il y a beaucoup d'autres types de données, comme les dates,
+# les séries temporelles, etc ...
+
+
+
+#######################################
+# Variables, boucles , if/else
+#######################################
+
+# Une variable est comme une boîte dans laquelle on garde une valeur
+# pour l'utiliser plus tard.
+# Nous appellons ça "assigner" une valeur à une variable.
+# Avoir des variables nous permet d'écrire des boucles, des fonctions, et
+# des instructions conditionnelles (if/else)
+
+# LES VARIABLES
+# Beaucoup de façons d'assigner des choses :
+x = 5 # c'est correct
+y <- "1" # c'est préféré
+TRUE -> z # ça marche mais c'est bizarre
+
+# LES BOUCLES
+# Il y a les boucles for :
+for (i in 1:4) {
+  print(i)
+}
+# Il y a les boucles while :
+a <- 10
+while (a > 4) {
+    cat(a, "...", sep = "")
+    a <- a - 1
+}
+# Gardez à l'esprit que les boucles for et while s'exécutent lentement
+# en R.
+# Des opérations sur la totalité d'un vecteur (ex une ligne entière,
+# une colonne entière),
+# ou les fonctions de type apply() (nous en parlerons plus tard),
+# sont préférées.
+
+# IF/ELSE
+# Encore une fois assez standard
+if (4 > 3) {
+    print("4 is greater than 3")
+} else {
+    print("4 is not greater than 3")
+}
+# =>
+# [1] "4 is greater than 3"
+
+# LES FONCTIONS
+# se définissent comme ceci :
+jiggle <- function(x) {
+    x = x + rnorm(1, sd=.1)	# ajoute un peu de bruit (contrôlé)
+    return(x)
+}
+# Appelées comme n'importe quelles autres fonction R :
+jiggle(5)	# 5±ε. After set.seed(2716057), jiggle(5)==5.005043
+
+
+
+##########################################################################
+# Les structures de données : les vecteurs, les matrices,
+# les data frames et les tableaux
+##########################################################################
+
+# À UNE DIMENSION
+
+# Commençons par le tout début, et avec quelque chose que
+# vous connaissez déjà : les vecteurs.
+vec <- c(8, 9, 10, 11)
+vec	#  8  9 10 11
+# Nous demandons des éléments spécifiques en les mettant entre crochets
+# (Notez que R commence à compter à partir de 1)
+vec[1]		# 8
+letters[18]	# "r"
+LETTERS[13]	# "M"
+month.name[9]	# "September"
+c(6, 8, 7, 5, 3, 0, 9)[3]	# 7
+# Nous pouvons également rechercher des indices de composants spécifiques,
+which(vec %% 2 == 0)	# 1 3
+# Récupèrer seulement les premières ou dernières entrées du vecteur,
+head(vec, 1)	# 8
+tail(vec, 2)	# 10 11
+# ou vérifier si un certaine valeur est dans le vecteur
+any(vec == 10) # TRUE
+# Si un index "dépasse" vous obtiendrez NA :
+vec[6]	# NA
+# Vous pouvez trouver la longueur de votre vecteur avec length()
+length(vec)	# 4
+# Vous pouvez réaliser des opérations sur des vecteurs entiers ou des
+# sous-ensembles de vecteurs
+vec * 4	# 16 20 24 28
+vec[2:3] * 5	# 25 30
+any(vec[2:3] == 8) # FALSE
+# Et R a beaucoup de méthodes statistiques pré-construites pour les vecteurs :
+mean(vec)	# 9.5
+var(vec)	# 1.666667
+sd(vec)		# 1.290994
+max(vec)	# 11
+min(vec)	# 8
+sum(vec)	# 38
+# Quelques fonctions préconstruites sympas supplémentaires :
+5:15	# 5  6  7  8  9 10 11 12 13 14 15
+seq(from=0, to=31337, by=1337)
+# =>
+#  [1]     0  1337  2674  4011  5348  6685  8022  9359 10696 12033 13370 14707
+# [13] 16044 17381 18718 20055 21392 22729 24066 25403 26740 28077 29414 30751
+
+# À DEUX DIMENSIONS (TOUT DANS UNE CLASSE)
+
+# Vous pouvez créer une matrice à partir d'entrées du même type comme ceci :
+mat <- matrix(nrow = 3, ncol = 2, c(1,2,3,4,5,6))
+mat
+# =>
+#      [,1] [,2]
+# [1,]    1    4
+# [2,]    2    5
+# [3,]    3    6
+# Différemment du vecteur, la classe d'une matrice est "matrix",
+# peut importe ce qu'elle contient
+class(mat) # => "matrix"
+# Récupérer la première ligne
+mat[1,]	# 1 4
+# Réaliser une opération sur la première colonne
+3 * mat[,1]	# 3 6 9
+# Demander une cellule spécifique
+mat[3,2]	# 6
+
+# Transposer la matrice entière
+t(mat)
+# =>
+#      [,1] [,2] [,3]
+# [1,]    1    2    3
+# [2,]    4    5    6
+
+# La multiplication de matrices
+mat %*% t(mat)
+# =>
+#      [,1] [,2] [,3]
+# [1,]   17   22   27
+# [2,]   22   29   36
+# [3,]   27   36   45
+
+# cbind() colle des vecteurs ensemble en colonne pour faire une matrice
+mat2 <- cbind(1:4, c("dog", "cat", "bird", "dog"))
+mat2
+# =>
+#      [,1] [,2]
+# [1,] "1"  "dog"
+# [2,] "2"  "cat"
+# [3,] "3"  "bird"
+# [4,] "4"  "dog"
+class(mat2)	# matrix
+# Encore une fois regardez ce qui se passe !
+# Parce que les matrices peuvent contenir des entrées de toutes sortes de
+# classes, tout sera converti en classe caractère
+c(class(mat2[,1]), class(mat2[,2]))
+
+# rbind() colle des vecteurs ensemble par lignes pour faire une matrice
+mat3 <- rbind(c(1,2,4,5), c(6,7,0,4))
+mat3
+# =>
+#      [,1] [,2] [,3] [,4]
+# [1,]    1    2    4    5
+# [2,]    6    7    0    4
+# Ah, tout de la même classe. Pas de coercitions. Beaucoup mieux.
+
+# À DEUX DIMENSIONS (DE CLASSES DIFFÉRENTES)
+
+# Pour des colonnes de différents types, utiliser une data frame
+# Cette structure de données est si utile pour la programmation statistique,
+# qu'une version a été ajoutée à Python dans le paquet "pandas".
+
+students <- data.frame(c("Cedric","Fred","George","Cho","Draco","Ginny"),
+                       c(3,2,2,1,0,-1),
+                       c("H", "G", "G", "R", "S", "G"))
+names(students) <- c("name", "year", "house") # name the columns
+class(students)	# "data.frame"
+students
+# =>
+#     name year house
+# 1 Cedric    3     H
+# 2   Fred    2     G
+# 3 George    2     G
+# 4    Cho    1     R
+# 5  Draco    0     S
+# 6  Ginny   -1     G
+class(students$year)	# "numeric"
+class(students[,3])	# "factor"
+# Trouver les dimensions
+nrow(students)	# 6
+ncol(students)	# 3
+dim(students)	# 6 3
+# La fonction data.frame() convertit les vecteurs caractères en vecteurs de
+# facteurs par défaut; désactiver cette fonction en règlant
+# stringsAsFactors = FALSE quand vous créer la data.frame
+?data.frame
+
+# Il y a plusieurs façons de subdiviser les data frames,
+# toutes subtilement différentes
+students$year	# 3  2  2  1  0 -1
+students[,2]	# 3  2  2  1  0 -1
+students[,"year"]	# 3  2  2  1  0 -1
+
+# Une version améliorée de la structure data.frame est data.table.
+# Si vous travaillez avec des données volumineuses ou des panels, ou avez
+# besoin de fusionner quelques ensembles de données, data.table peut être
+# un bon choix. Ici un tour éclair :
+install.packages("data.table") # télécharge le paquet depuis CRAN
+require(data.table) # le charge
+students <- as.data.table(students)
+students # regardez la différence à l'impression
+# =>
+#      name year house
+# 1: Cedric    3     H
+# 2:   Fred    2     G
+# 3: George    2     G
+# 4:    Cho    1     R
+# 5:  Draco    0     S
+# 6:  Ginny   -1     G
+students[name=="Ginny"] # obtiens les lignes avec name == "Ginny"
+# =>
+#     name year house
+# 1: Ginny   -1     G
+students[year==2] # obtiens les lignes avec year == 2
+# =>
+#      name year house
+# 1:   Fred    2     G
+# 2: George    2     G
+# data.table facilite la fusion entre deux ensembles de données
+# Faisons une autre data.table pour fusionner students
+founders <- data.table(house=c("G","H","R","S"),
+                       founder=c("Godric","Helga","Rowena","Salazar"))
+founders
+# =>
+#    house founder
+# 1:     G  Godric
+# 2:     H   Helga
+# 3:     R  Rowena
+# 4:     S Salazar
+setkey(students, house)
+setkey(founders, house)
+students <- founders[students] # merge les deux ensembles de données qui matchent "house"
+setnames(students, c("house","houseFounderName","studentName","year"))
+students[,order(c("name","year","house","houseFounderName")), with=F]
+# =>
+#    studentName year house houseFounderName
+# 1:        Fred    2     G           Godric
+# 2:      George    2     G           Godric
+# 3:       Ginny   -1     G           Godric
+# 4:      Cedric    3     H            Helga
+# 5:         Cho    1     R           Rowena
+# 6:       Draco    0     S          Salazar
+
+# data.table facilite le résumé des tableaux
+students[,sum(year),by=house]
+# =>
+#    house V1
+# 1:     G  3
+# 2:     H  3
+# 3:     R  1
+# 4:     S  0
+
+# Pour supprimer une colonne d'une data.frame ou data.table,
+# assignez-lui la valeur NULL
+students$houseFounderName <- NULL
+students
+# =>
+#    studentName year house
+# 1:        Fred    2     G
+# 2:      George    2     G
+# 3:       Ginny   -1     G
+# 4:      Cedric    3     H
+# 5:         Cho    1     R
+# 6:       Draco    0     S
+
+# Supprimer une ligne en subdivisant
+# En utilisant data.table :
+students[studentName != "Draco"]
+# =>
+#    house studentName year
+# 1:     G        Fred    2
+# 2:     G      George    2
+# 3:     G       Ginny   -1
+# 4:     H      Cedric    3
+# 5:     R         Cho    1
+# En utilisant data.frame :
+students <- as.data.frame(students)
+students[students$house != "G",]
+# =>
+#   house houseFounderName studentName year
+# 4     H            Helga      Cedric    3
+# 5     R           Rowena         Cho    1
+# 6     S          Salazar       Draco    0
+
+# MULTI-DIMENSIONNELLE (TOUS ÉLÉMENTS D'UN TYPE)
+
+# Les arrays créent des tableaux de n dimensions.
+# Tous les éléments doivent être du même type.
+# Vous pouvez faire un tableau à 2 dimensions (une sorte de matrice)
+array(c(c(1,2,4,5),c(8,9,3,6)), dim=c(2,4))
+# =>
+#      [,1] [,2] [,3] [,4]
+# [1,]    1    4    8    3
+# [2,]    2    5    9    6
+# Vous pouvez aussi utiliser array pour faire des matrices à 3 dimensions :
+array(c(c(c(2,300,4),c(8,9,0)),c(c(5,60,0),c(66,7,847))), dim=c(3,2,2))
+# =>
+# , , 1
+#
+#      [,1] [,2]
+# [1,]    2    8
+# [2,]  300    9
+# [3,]    4    0
+#
+# , , 2
+#
+#      [,1] [,2]
+# [1,]    5   66
+# [2,]   60    7
+# [3,]    0  847
+
+# LES LISTES (MULTI-DIMENSIONNELLES, ÉVENTUELLEMMENT DÉCHIRÉES,
+# DE DIFFÉRENTS TYPES)
+
+# Enfin, R a des listes (de vecteurs)
+list1 <- list(time = 1:40)
+list1$price = c(rnorm(40,.5*list1$time,4)) # random
+list1
+# Vous pouvez obtenir des éléments de la liste comme ceci
+list1$time # une façon
+list1[["time"]] # une autre façon
+list1[[1]] # encore une façon différente
+# =>
+#  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
+# [34] 34 35 36 37 38 39 40
+# Vous pouvez subdiviser les éléments d'une liste comme n'importe quel vecteur
+list1$price[4]
+
+# Les listes ne sont pas les structures de données les plus efficaces
+# à utiliser avec R ;
+# À moins d'avoir une très bonne raison, vous devriez utiliser data.frames
+# Les listes sont souvent retournées par des fonctions qui effectuent
+# des régressions linéaires.
+
+##########################################
+# La famille de fonction apply()
+##########################################
+
+# Vous vous rappelez mat ?
+mat
+# =>
+#      [,1] [,2]
+# [1,]    1    4
+# [2,]    2    5
+# [3,]    3    6
+# Utilisez apply(X, MARGIN, FUN) pour appliquer la fonction FUN à la matrice X
+# sur les lignes (MAR = 1) ou les colonnes (MAR = 2)
+# R exécute FUN à chaque lignes (ou colonnes) de X, beaucoup plus rapidement
+# que le ferait une boucle for ou while
+apply(mat, MAR = 2, jiggle)
+# =>
+#      [,1] [,2]
+# [1,]    3   15
+# [2,]    7   19
+# [3,]   11   23
+# D'autres fonctions : ?lapply, ?sapply
+
+# Ne soyez pas trop intimidé ; tout le monde reconnaît que c'est un peu déroutant
+
+# Le paquet plyr vise à remplacer (et améliorer !) la famille *apply().
+install.packages("plyr")
+require(plyr)
+?plyr
+
+
+
+############################
+# Charger des données
+############################
+
+# "pets.csv" est un fichier sur internet
+# (mais il pourrait être tout aussi facilement sur votre ordinateur)
+pets <- read.csv("http://learnxinyminutes.com/docs/pets.csv")
+pets
+head(pets, 2) # first two rows
+tail(pets, 1) # last row
+
+# Pour sauvegarder une data frame ou une matrice en fichier .csv
+write.csv(pets, "pets2.csv") # to make a new .csv file
+# définir le répertoire de travail avec setwd(), le récupérer avec getwd()
+
+# Essayez ?read.csv et ?write.csv pour plus d'informations
+
+
+
+################
+# Les tracés
+################
+
+# LES FONCTIONS DE TRACÉ PRÉCONSTRUITES
+# Les diagrammes de dispersion !
+plot(list1$time, list1$price, main = "fake data")
+# Les régressions !
+linearModel <- lm(price  ~ time, data = list1)
+linearModel # sort le résultat de la régression
+# Tracer une ligne de regression sur une tracé existant
+abline(linearModel, col = "red")
+# Obtenir une variété de diagnostiques sympas
+plot(linearModel)
+# Les histogrammes !
+hist(rpois(n = 10000, lambda = 5), col = "thistle")
+# Les diagrammes en bâtons !
+barplot(c(1,4,5,1,2), names.arg = c("red","blue","purple","green","yellow"))
+
+# GGPLOT2
+# Mais ceux-ci ne sont même pas les plus jolis tracés de R
+# Essayez le paquet ggplot2 pour d'avantages de graphiques
+install.packages("ggplot2")
+require(ggplot2)
+?ggplot2
+pp <- ggplot(students, aes(x=house))
+pp + geom_histogram()
+ll <- as.data.table(list1)
+pp <- ggplot(ll, aes(x=time,price))
+pp + geom_point()
+# ggplot2 a une documentation excellente
+#(disponible sur http://docs.ggplot2.org/current/)
+
+
+
+```
+
+## Comment obtenir R ?
+
+* Obtiens R et R GUI depuis [http://www.r-project.org/](http://www.r-project.org/)
+* [RStudio](http://www.rstudio.com/ide/) est un autre GUI

fr-fr/typescript-fr.html.markdown

@@ -0,0 +1,174 @@
+---
+language: TypeScript
+contributors:
+    - ["Philippe Vlérick", "https://github.com/pvlerick"]
+translators:
+    - ["Alois de Gouvello", "https://github.com/aloisdg"]
+filename: learntypescript-fr.ts
+lang: fr-fr
+---
+
+TypeScript est un langage visant à faciliter le développement d'applications larges et scalables, écrites en JavaScript.
+TypeScript ajoute des concepts classiques comme les classes, les modules, les interfaces, les génériques et le typage statique (optionnel) à JavaScript.
+C'est une surcouche de JavaScript : tout le code JavaScript est valide en TypeScript ce qui permet de l'ajouter de façon transparente à n'importe quel projet. Le code TypeScript est transcompilé en JavaScript par le compilateur.
+
+Cet article se concentrera seulement sur la syntaxe supplémentaire de TypeScript, plutôt que celle de [JavaScript] (../javascript/).
+
+Pour tester le compilateur de TypeScript, rendez-vous au [Playground] (http://www.typescriptlang.org/Playground) où vous pourrez coder, profiter d'une autocomplétion et accéder directement au rendu JavaScript.
+
+```js
+// Il y a 3 types basiques en TypeScript
+var isDone: boolean = false;
+var lines: number = 42;
+var name: string = "Anders";
+
+// Si nous ne pouvons pas déterminer le type, on utilise `Any`
+var notSure: any = 4;
+notSure = "maybe a string instead";
+notSure = false; // ok, définitivement un booléen
+
+// Pour les collections, il y a les tableaux typés et les tableaux génériques
+var list: number[] = [1, 2, 3]; // Un tableaux typé
+var list: Array<number> = [1, 2, 3]; // un tableau générique
+
+// Pour les énumeration
+enum Color { Red, Green, Blue };
+var c: Color = Color.Green;
+
+// Enfin, `void` est utilisé dans le cas spécifique
+// d'une fonction ne retournant rien
+function bigHorribleAlert(): void {
+  alert("Je suis une petite boîte ennuyeuse !");
+}
+
+// Les fonctions sont des entités de première classe. Le langage supporte
+// les expressions lambda et utilise l'inférence de type
+
+// Les fonctions ci-dessous sont équivalentes, une signature identique
+// sera inférée par le compilateur, et le même JavaScript sera généré
+var f1 = function(i: number): number { return i * i; }
+// Retourne un type inféré
+var f2 = function(i: number) { return i * i; }
+var f3 = (i: number): number => { return i * i; }
+// Retourne un type inféré
+var f4 = (i: number) => { return i * i; }
+// Retourne un type inféré, ici le mot clé `return` n'est pas nécessaire
+var f5 = (i: number) =>  i * i;
+
+// Les interfaces sont structurées, tout les objets qui ont ces propriétés
+// sont compatible avec l'interface
+interface Person {
+  name: string;
+  // Les propriétés optionnelles sont identifiées avec un "?"
+  age?: number;
+  // Et bien sûr, les fonctions
+  move(): void;
+}
+
+// Un objet implémentant l'interface "Person" peut être traité comme 
+// une Person car il a les propriétés "name" et "move"
+var p: Person = { name: "Bobby", move: () => {} };
+// Des objets implémentants la propriété optionnelle :
+// valide car "age" est un nombre
+var validPerson: Person = { name: "Bobby", age: 42, move: () => {} };
+// invalide car "age" n'est pas un nombre
+var invalidPerson: Person = { name: "Bobby", age: true };
+
+// Les interfaces peuvent aussi décrire un type de fonction
+interface SearchFunc {
+  (source: string, subString: string): boolean;
+}
+
+// Seul les types des paramètres sont importants. Les noms ne le sont pas.
+var mySearch: SearchFunc;
+mySearch = function(src: string, sub: string) {
+  return src.search(sub) != -1;
+}
+
+// Les membres des classes sont publiques par défaut.
+class Point {
+    // Propriétés
+    x: number;
+
+    // Constructeur - Les mots clés "public" et "private" dans ce contexte
+    //  génèrent le code de la propriété et son initialisation dans le
+    // constructeur. Ici, "y" sera défini de la même façon que "x",
+    // mais avec moins de code. Les valeurs par défaut sont supportées.
+    constructor(x: number, public y: number = 0) {
+        this.x = x;
+    }
+
+    // Fonctions
+    dist() { return Math.sqrt(this.x * this.x + this.y * this.y); }
+
+    // Membres statiques
+    static origin = new Point(0, 0);
+}
+
+var p1 = new Point(10 ,20);
+var p2 = new Point(25); // y sera 0
+
+// Héritage
+class Point3D extends Point {
+    constructor(x: number, y: number, public z: number = 0) {
+        // Un appel explicite au constructeur de la super classe
+        // est obligatoire.
+        super(x, y);
+    }
+
+    // Redéfinition
+    dist() {
+        var d = super.dist();
+        return Math.sqrt(d * d + this.z * this.z);
+    }
+}
+
+// Modules, "." peut être utilisé comme un séparateur de sous modules.
+module Geometry {
+  export class Square {
+    constructor(public sideLength: number = 0) {
+    }
+    area() {
+      return Math.pow(this.sideLength, 2);
+    }
+  }
+}
+
+var s1 = new Geometry.Square(5);
+
+// Alias local pour référencer un module
+import G = Geometry;
+
+var s2 = new G.Square(10);
+
+// Génériques
+// Classes
+class Tuple<T1, T2> {
+    constructor(public item1: T1, public item2: T2) {
+    }
+}
+
+// Interfaces
+interface Pair<T> {
+    item1: T;
+    item2: T;
+}
+
+// Et fonctions
+var pairToTuple = function<T>(p: Pair<T>) {
+    return new Tuple(p.item1, p.item2);
+};
+
+var tuple = pairToTuple({ item1:"hello", item2:"world"});
+
+// Inclure des références à un fichier :
+/// <reference path="jquery.d.ts" />
+
+```
+
+## Lectures complémentaires
+ * [Site officiel de TypeScript] (http://www.typescriptlang.org/)
+ * [Spécification du langage TypeScript (pdf)] (http://go.microsoft.com/fwlink/?LinkId=267238)
+ * [Anders Hejlsberg - Introducing TypeScript on Channel 9] (http://channel9.msdn.com/posts/Anders-Hejlsberg-Introducing-TypeScript)
+ * [Code source sur GitHub] (https://github.com/Microsoft/TypeScript)
+ * [Definitely Typed - repository for type definitions] (http://definitelytyped.org/)

git.html.markdown

@@ -79,6 +79,11 @@ this pointer will automatically update and point to the latest commit.
 HEAD is a pointer that points to the current branch. A repository only has 1 *active* HEAD.
 head is a pointer that points to any commit. A repository can have any number of heads.
 
+###Stages of Git
+* Modified - Changes have been made to a file but file has not been committed to Git Database yet
+* Staged - Marks a modified file to go into your next commit snapshot
+* Committed - Files have been committed to the Git Database
+
 ### Conceptual Resources
 
 * [Git For Computer Scientists](http://eagain.net/articles/git-for-computer-scientists/)
@@ -131,6 +136,10 @@ $ git help -a
 $ git help add
 $ git help commit
 $ git help init
+# or git <command_here> --help
+$ git add --help
+$ git commit --help
+$ git init --help
 ```
 
 ### status
@@ -149,8 +158,8 @@ $ git help status
 
 ### add
 
-To add files to the current working tree/directory/repo. If you do not `git add` new files to the
+To add files to the staging area/index. If you do not `git add` new files to the
-working tree/directory, they will not be included in commits!
+staging area/index, they will not be included in commits!
 
 ```bash
 # add a file in your current working directory
@@ -163,6 +172,8 @@ $ git add /path/to/file/HelloWorld.c
 $ git add ./*.java
 ```
 
+This only adds a file to the staging area/index, it doesn't commit it to the working directory/repo.
+
 ### branch
 
 Manage your branches. You can view, edit, create, delete branches using this command.
@@ -462,3 +473,5 @@ $ git rm /pather/to/the/file/HelloWorld.c
 * [GitGuys](http://www.gitguys.com/)
 
 * [Git - the simple guide](http://rogerdudler.github.io/git-guide/index.html)
+
+* [Pro Git](http://www.git-scm.com/book/en/v2)

groovy.html.markdown

@@ -6,7 +6,7 @@ contributors:
 filename: learngroovy.groovy
 ---
 
-Groovy - A dynamic language for the Java platform [Read more here.](http://groovy.codehaus.org)
+Groovy - A dynamic language for the Java platform [Read more here.](http://www.groovy-lang.org/)
 
 ```groovy
 
@@ -231,7 +231,7 @@ for ( e in map ) {
   Operators
 
   Operator Overloading for a list of the common operators that Groovy supports:
-  http://groovy.codehaus.org/Operator+Overloading
+  http://www.groovy-lang.org/operators.html#Operator-Overloading
 
   Helpful groovy operators
 */
@@ -249,7 +249,7 @@ def username = user?.username
   A Groovy Closure is like a "code block" or a method pointer. It is a piece of
   code that is defined and then executed at a later point.
 
-  More info at: http://groovy.codehaus.org/Closures+-+Formal+Definition
+  More info at: http://www.groovy-lang.org/closures.html
 */
 //Example:
 def clos = { println "Hello World!" }
@@ -405,11 +405,11 @@ assert sum(2,5) == 7
 
 ## Further resources
 
-[Groovy documentation](http://groovy.codehaus.org/Documentation)
+[Groovy documentation](http://www.groovy-lang.org/documentation.html)
 
 [Groovy web console](http://groovyconsole.appspot.com/)
 
-Join a [Groovy user group](http://groovy.codehaus.org/User+Groups)
+Join a [Groovy user group](http://www.groovy-lang.org/usergroups.html)
 
 ## Books
 

haskell.html.markdown

@@ -282,7 +282,7 @@ foldl (\x y -> 2*x + y) 4 [1,2,3] -- 43
 foldr (\x y -> 2*x + y) 4 [1,2,3] -- 16
 
 -- This is now the same as
-(2 * 3 + (2 * 2 + (2 * 1 + 4)))
+(2 * 1 + (2 * 2 + (2 * 3 + 4)))
 
 ----------------------------------------------------
 -- 7. Data Types

haxe.html.markdown

@@ -323,7 +323,7 @@ class LearnHaxe3{
         var  l = 0;
         do{
             trace("do statement always runs at least once");
-        } while (i > 0);
+        } while (l > 0);
 
         // for loop
         /*
@@ -340,7 +340,7 @@ class LearnHaxe3{
         // (more on ranges later as well)
         var n = ['foo', 'bar', 'baz'];
         for (val in 0...n.length){
-            trace(val + " is the value for val (an index for m)");
+            trace(val + " is the value for val (an index for n)");
         }
 
 
@@ -375,7 +375,7 @@ class LearnHaxe3{
             case "rex"  : favorite_thing = "shoe";
             case "spot" : favorite_thing = "tennis ball";
             default     : favorite_thing = "some unknown treat";
-            // case _   : "some unknown treat"; // same as default
+            // case _   : favorite_thing = "some unknown treat"; // same as default
         }
         // The "_" case above is a "wildcard" value
         // that will match anything.
@@ -397,7 +397,7 @@ class LearnHaxe3{
         // if statements
         var k = if (true) 10 else 20;
 
-        trace("K equals ", k); // outputs 10
+        trace("k equals ", k); // outputs 10
 
         var other_favorite_thing = switch(my_dog_name) {
             case "fido" : "teddy";
@@ -495,8 +495,10 @@ class LearnHaxe3{
         // foo_instance.public_read = 4; // this will throw an error if uncommented:
         // trace(foo_instance.public_write); // as will this.
 
-        trace(foo_instance + " is the value for foo_instance"); // calls the toString method
+        // calls the toString method:
-        trace(foo_instance.toString() + " is the value for foo_instance.toString()"); // same thing
+        trace(foo_instance + " is the value for foo_instance");
+        // same thing:
+        trace(foo_instance.toString() + " is the value for foo_instance.toString()");
 
 
         /*
@@ -524,8 +526,8 @@ class LearnHaxe3{
  */
 class FooClass extends BarClass implements BarInterface{
     public var public_any:Int; // public variables are accessible anywhere
-    public var public_read (default,null): Int; // use this style to only enable public read
+    public var public_read (default, null): Int; // enable only public read
-    public var public_write (null, default): Int; // or public write
+    public var public_write (null, default): Int; // or only public write
     public var property (get, set): Int; // use this style to enable getters/setters
 
     // private variables are not available outside the class.
@@ -534,9 +536,10 @@ class FooClass extends BarClass implements BarInterface{
 
     // a public constructor
     public function new(arg:Int){
-        super(); // call the constructor of the parent object, since we extended BarClass
+        // call the constructor of the parent object, since we extended BarClass:
+        super();
 
-        this.public_any= 0;
+        this.public_any = 0;
         this._private = arg;
 
     }

it-it/bash-it.html.markdown

@@ -0,0 +1,275 @@
+---
+category: tool
+tool: bash
+contributors:
+    - ["Max Yankov", "https://github.com/golergka"]
+    - ["Darren Lin", "https://github.com/CogBear"]
+    - ["Alexandre Medeiros", "http://alemedeiros.sdf.org"]
+    - ["Denis Arh", "https://github.com/darh"]
+    - ["akirahirose", "https://twitter.com/akirahirose"]
+    - ["Anton Strömkvist", "http://lutic.org/"]
+    - ["Rahil Momin", "https://github.com/iamrahil"]
+    - ["Gregrory Kielian", "https://github.com/gskielian"]
+filename: LearnBash.sh
+translators:
+    - ["Robert Margelli", "http://github.com/sinkswim/"]
+lang: it-it
+---
+
+Bash è il nome della shell di unix, la quale è stata distribuita anche come shell del sistema oprativo GNU e la shell di default su Linux e Mac OS X.
+Quasi tutti gli esempi sottostanti possono fare parte di uno shell script o eseguiti direttamente nella shell.
+
+[Per saperne di piu'.](http://www.gnu.org/software/bash/manual/bashref.html)
+
+```bash
+#!/bin/bash
+# La prima riga dello script è lo shebang il quale dice al sistema come eseguire
+# lo script: http://it.wikipedia.org/wiki/Shabang
+# Come avrai già immaginato, i commenti iniziano con #. Lo shebang stesso è un commento.
+
+# Semplice esempio ciao mondo:
+echo Ciao mondo!
+
+# Ogni comando inizia su una nuova riga, o dopo un punto e virgola:
+echo 'Questa è la prima riga'; echo 'Questa è la seconda riga'
+
+# Per dichiarare una variabile:
+VARIABILE="Una stringa"
+
+# Ma non così:
+VARIABILE = "Una stringa"
+# Bash stabilirà che VARIABILE è un comando da eseguire e darà un errore
+# perchè non esiste.
+
+# Usare la variabile:
+echo $VARIABILE
+echo "$VARIABILE"
+echo '$VARIABILE'
+# Quando usi la variabile stessa - assegnala, esportala, oppure — scrivi
+# il suo nome senza $. Se vuoi usare il valore della variabile, devi usare $.
+# Nota che ' (singolo apice) non espande le variabili!
+
+# Sostituzione di stringhe nelle variabili
+echo ${VARIABILE/Una/A}
+# Questo sostituirà la prima occorrenza di "Una" con "La"
+
+# Sottostringa di una variabile
+echo ${VARIABILE:0:7}
+# Questo ritornerà solamente i primi 7 caratteri
+
+# Valore di default per la variabile
+echo ${FOO:-"ValoreDiDefaultSeFOOMancaOÈ Vuoto"}
+# Questo funziona per null (FOO=), stringa vuota (FOO=""), zero (FOO=0) ritorna 0
+
+# Variabili builtin:
+# Ci sono delle variabili builtin molto utili, come
+echo "Valore di ritorno dell'ultimo programma eseguito: $?"
+echo "PID dello script: $$"
+echo "Numero di argomenti: $#"
+echo "Argomenti dello script: $@"
+echo "Argomenti dello script separati in variabili distinte: $1 $2..."
+
+# Leggere un valore di input:
+echo "Come ti chiami?"
+read NOME # Nota che non abbiamo dovuto dichiarare una nuova variabile
+echo Ciao, $NOME!
+
+# Classica struttura if:
+# usa 'man test' per maggiori informazioni sulle condizionali
+if [ $NOME -ne $USER ]
+then
+    echo "Il tuo nome non è lo username"
+else
+    echo "Il tuo nome è lo username"
+fi
+
+# C'è anche l'esecuzione condizionale
+echo "Sempre eseguito" || echo "Eseguito solo se la prima condizione fallisce"
+echo "Sempre eseguito" && echo "Eseguito solo se la prima condizione NON fallisce"
+
+# Per usare && e || con l'if, c'è bisogno di piu' paia di parentesi quadre:
+if [ $NOME == "Steve" ] && [ $ETA -eq 15 ]
+then
+    echo "Questo verrà eseguito se $NOME è Steve E $ETA è 15."
+fi
+
+if [ $NOME == "Daniya" ] || [ $NOME == "Zach" ]
+then
+    echo "Questo verrà eseguito se $NAME è Daniya O Zach."
+fi
+
+# Le espressioni sono nel seguente formato:
+echo $(( 10 + 5 ))
+
+# A differenza di altri linguaggi di programmazione, bash è una shell - quindi lavora nel contesto
+# della cartella corrente. Puoi elencare i file e le cartelle nella cartella
+# corrente con il comando ls:
+ls
+
+# Questi comandi hanno opzioni che controllano la loro esecuzione:
+ls -l # Elenca tutti i file e le cartelle su una riga separata
+
+# I risultati del comando precedente possono essere passati al comando successivo come input.
+# Il comando grep filtra l'input con il pattern passato. Ecco come possiamo elencare i
+# file .txt nella cartella corrente:
+ls -l | grep "\.txt"
+
+# Puoi redirezionare l'input e l'output del comando (stdin, stdout, e stderr).
+# Leggi da stdin finchè ^EOF$ e sovrascrivi hello.py con le righe
+# comprese tra "EOF":
+cat > hello.py << EOF
+#!/usr/bin/env python
+from __future__ import print_function
+import sys
+print("#stdout", file=sys.stdout)
+print("#stderr", file=sys.stderr)
+for line in sys.stdin:
+    print(line, file=sys.stdout)
+EOF
+
+# Esegui hello.py con diverse redirezioni stdin, stdout, e stderr:
+python hello.py < "input.in"
+python hello.py > "output.out"
+python hello.py 2> "error.err"
+python hello.py > "output-and-error.log" 2>&1
+python hello.py > /dev/null 2>&1
+# Lo output error sovrascriverà il file se esiste,
+# se invece vuoi appendere usa ">>":
+python hello.py >> "output.out" 2>> "error.err"
+
+# Sovrascrivi output.txt, appendi a error.err, e conta le righe:
+info bash 'Basic Shell Features' 'Redirections' > output.out 2>> error.err
+wc -l output.out error.err
+
+# Esegui un comando e stampa il suo file descriptor (esempio: /dev/fd/123)
+# vedi: man fd
+echo <(echo "#ciaomondo")
+
+# Sovrascrivi output.txt con "#helloworld":
+cat > output.out <(echo "#helloworld")
+echo "#helloworld" > output.out
+echo "#helloworld" | cat > output.out
+echo "#helloworld" | tee output.out >/dev/null
+
+# Pulisci i file temporanei verbosamente (aggiungi '-i' per la modalità interattiva)
+rm -v output.out error.err output-and-error.log
+
+# I comandi possono essere sostituiti con altri comandi usando $( ):
+# Il comando seguente mostra il numero di file e cartelle nella
+# cartella corrente.
+echo "Ci sono $(ls | wc -l) oggetti qui."
+
+# Lo stesso puo' essere usato usando backticks `` ma non possono essere innestati - il modo migliore
+# è usando $( ).
+echo "Ci sono `ls | wc -l` oggetti qui."
+
+# Bash utilizza uno statemente case che funziona in maniera simile allo switch in Java e C++:
+case "$VARIABILE" in 
+    #Lista di pattern per le condizioni che vuoi soddisfare
+    0) echo "C'è uno zero.";;
+    1) echo "C'è un uno.";;
+    *) echo "Non è null.";;
+esac
+
+# I cicli for iterano per ogni argomento fornito:
+# I contenuti di $VARIABILE sono stampati tre volte.
+for VARIABILE in {1..3}
+do
+    echo "$VARIABILE"
+done
+
+# O scrivilo con il "ciclo for tradizionale":
+for ((a=1; a <= 3; a++))
+do
+    echo $a
+done
+
+# Possono essere usati anche per agire su file..
+# Questo eseguirà il comando 'cat' su file1 e file2
+for VARIABILE in file1 file2
+do
+    cat "$VARIABILE"
+done
+
+# ..o dall'output di un comando
+# Questo eseguirà cat sull'output di ls.
+for OUTPUT in $(ls)
+do
+    cat "$OUTPUT"
+done
+
+# while loop:
+while [ true ]
+do
+    echo "corpo del loop..."
+    break
+done
+
+# Puoi anche definire funzioni
+# Definizione:
+function foo ()
+{
+    echo "Gli argomenti funzionano come gli argomenti dello script: $@"
+    echo "E: $1 $2..."
+    echo "Questa è una funzione"
+    return 0
+}
+
+# o semplicemente
+bar ()
+{
+    echo "Un altro modo per dichiarare funzioni!"
+    return 0
+}
+
+# Per chiamare la funzione
+foo "Il mio nome è" $NOME
+
+# Ci sono un sacco di comandi utili che dovresti imparare:
+# stampa le ultime 10 righe di file.txt
+tail -n 10 file.txt
+# stampa le prime 10 righe di file.txt
+head -n 10 file.txt
+# ordina le righe di file.txt
+sort file.txt
+# riporta o ometti le righe ripetute, con -d le riporta
+uniq -d file.txt
+# stampa solamente la prima colonna prima del carattere ','
+cut -d ',' -f 1 file.txt
+# sostituisce ogni occorrenza di 'okay' con 'great' in file.txt (compatible con le regex)
+sed -i 's/okay/great/g' file.txt
+# stampa su stdout tutte le righe di file.txt che soddisfano una certa regex
+# L'esempio stampa le righe che iniziano con "foo" e che finiscono con "bar"
+grep "^foo.*bar$" file.txt
+# passa l'opzione "-c" per stampare invece il numero delle righe che soddisfano la regex
+grep -c "^foo.*bar$" file.txt
+# se vuoi letteralmente cercare la stringa,
+# e non la regex, usa fgrep (o grep -F)
+fgrep "^foo.*bar$" file.txt 
+
+
+# Leggi la documentazione dei builtin di bash con il builtin 'help' di bash:
+help
+help help
+help for
+help return
+help source
+help .
+
+# Leggi la manpage di bash con man
+apropos bash
+man 1 bash
+man bash
+
+# Leggi la documentazione con info (? per help)
+apropos info | grep '^info.*('
+man info
+info info
+info 5 info
+
+# Leggi la documentazione di bash:
+info bash
+info bash 'Bash Features'
+info bash 6
+info --apropos bash
+```

it-it/c++-it.html.markdown

@@ -0,0 +1,720 @@
+---
+language: c++
+filename: learncpp-it.cpp
+contributors:
+    - ["Steven Basart", "http://github.com/xksteven"]
+    - ["Matt Kline", "https://github.com/mrkline"]
+translators:
+    - ["Robert Margelli", "http://github.com/sinkswim/"]
+lang: it-it
+---
+
+Il C++ è un linguaggio di programmazione il quale,
+[secondo il suo inventore Bjarne Stroustrup](http://channel9.msdn.com/Events/Lang-NEXT/Lang-NEXT-2014/Keynote),
+è stato progettato per
+
+- essere un "miglior C"
+- supportare l'astrazione dei dati
+- supportare la programmazione orientata agli oggetti
+- supportare la programmazione generica
+
+Nonostante la sintassi possa risultare più difficile o complessa di linguaggi più recenti,
+è usato in maniera vasta poichè viene compilato in istruzioni macchina che possono
+essere eseguite direttamente dal processore ed offre un controllo stretto sull'hardware (come il linguaggio C)
+ed allo stesso tempo offre caratteristiche ad alto livello come i generici, le eccezioni, e le classi.
+Questa combinazione di velocità e funzionalità rende il C++
+uno dei più utilizzati linguaggi di programmazione.
+
+```c++
+//////////////////
+// Confronto con il C
+//////////////////
+
+// Il C++ è _quasi_ un superset del C e con esso condivide la sintassi di base per
+// la dichiarazione di variabili, tipi primitivi, e funzioni.
+
+// Proprio come nel C, l'inizio del programma è una funzione chiamata
+// main con un intero come tipo di ritorno,
+// Questo valore serve come stato d'uscita del programma.
+// Vedi http://it.wikipedia.org/wiki/Valore_di_uscita per maggiori informazioni.
+int main(int argc, char** argv)
+{
+    // Gli argomenti a linea di comando sono passati tramite argc e argv così come
+    // avviene in C.
+    // argc indica il numero di argomenti,
+    // e argv è un array di stringhe in stile-C (char*)
+    // che rappresenta gli argomenti.
+    // Il primo argomento è il nome che è stato assegnato al programma.
+    // argc e argv possono essere omessi se non hai bisogno di argomenti,
+    // in questa maniera la funzione avrà int main() come firma.
+
+    // Lo stato di uscita 0 indica successo.
+    return 0;
+}
+
+// Tuttavia, il C++ varia nei seguenti modi:
+
+// In C++, i caratteri come letterali sono da un byte.
+sizeof('c') == 1
+
+// In C, i caratteri come letterali sono della stessa dimensione degli interi.
+sizeof('c') == sizeof(10)
+
+
+// C++ ha prototipizzazione rigida
+void func(); // funziona che non accetta argomenti
+
+// In C
+void func(); // funzione che può accettare un qualsiasi numero di argomenti
+
+// Usa nullptr invece di NULL in C++
+int* ip = nullptr;
+
+// Gli header C standard sono disponibili in C++,
+// ma sono prefissati con "c" e non hanno il suffisso ".h".
+#include <cstdio>
+
+int main()
+{
+    printf("Ciao, mondo!\n");
+    return 0;
+}
+
+///////////////////////////////
+// Overloading per le funzioni
+//////////////////////////////
+
+// Il C++ supporta l'overloading per le funzioni
+// sia dato che ogni funzione accetta parametri diversi.
+
+void print(char const* myString)
+{
+    printf("Stringa %s\n", myString);
+}
+
+void print(int myInt)
+{
+    printf("Il mio int è %d", myInt);
+}
+
+int main()
+{
+    print("Ciao"); // Viene chiamata void print(const char*)
+    print(15); //  Viene chiamata void print(int)
+}
+
+////////////////////////
+// Argomenti di default
+///////////////////////
+
+// Puoi fornire argomenti di default per una funzione
+// se non sono forniti dal chiamante.
+
+void faiQualcosaConInteri(int a = 1, int b = 4)
+{
+    // fai qualcosa con gli interi qui
+}
+
+int main()
+{
+    faiQualcosaConInteri();      // a = 1,  b = 4
+    faiQualcosaConInteri(20);    // a = 20, b = 4
+    faiQualcosaConInteri(20, 5); // a = 20, b = 5
+}
+
+// Gli argomenti di default devono essere alla fine della lista degli argomenti.
+
+void dichiarazioneInvalida(int a = 1, int b) // Errore!
+{
+}
+
+
+/////////////
+// Namespaces
+/////////////
+
+// I namespaces forniscono visibilità separata per dichiarazioni di variabili, funzioni,
+// ed altro.
+// I namespaces possono essere annidati.
+
+namespace Primo {
+    namespace Annidato {
+        void foo()
+        {
+            printf("Questa è Primo::Annidato::foo\n");
+        }
+    } // fine di namespace Annidato
+} // fine di namespace Primo
+
+namespace Secondo {
+    void foo()
+    {
+        printf("Questa è Secondo::foo\n")
+    }
+}
+
+void foo()
+{
+    printf("Questa è foo globale\n");
+}
+
+int main()
+{
+    // Assume che tutto venga dal namespace "Secondo"
+    // a meno che non venga dichiarato altrimenti.
+    using namespace Secondo;
+
+    foo(); // stampa "Questa è Secondo::foo"
+    Primo::Annidato::foo(); // stampa "Questa è Primo::Annidato::foo"
+    ::foo(); // stampa "Questa è foo globale"
+}
+
+///////////////
+// Input/Output
+///////////////
+
+// L'input e l'output in C++ utilizza gli streams
+// cin, cout, e cerr i quali rappresentano stdin, stdout, e stderr.
+// << è l'operatore di inserzione >> è l'operatore di estrazione.
+
+#include <iostream> // Include gli streams di I/O
+
+using namespace std; // Gli streams sono nel namespace std (libreria standard)
+
+int main()
+{
+   int myInt;
+
+   // Stampa su stdout (o terminalee/schermo)
+   cout << "Inserisci il tuo numero preferito:\n";
+   // Prende l'input
+   cin >> myInt;
+
+   // cout può anche essere formattato
+   cout << "Il tuo numero preferito è " << myInt << "\n";
+   // stampa "Il tuo numero preferito è <myInt>"
+
+    cerr << "Usato per messaggi di errore";
+}
+
+////////////
+// Stringhe
+///////////
+
+// Le stringhe in C++ sono oggetti ed hanno molte funzioni membro
+#include <string>
+
+using namespace std; // Anche le stringhe sono contenute nel namespace std (libreria standard)
+
+string myString = "Ciao";
+string myOtherString = " Mondo";
+
+// + è usato per la concatenazione.
+cout << myString + myOtherString; // "Ciao Mondo"
+
+cout << myString + " Bella"; // "Ciao Bella"
+
+// le stringhe in C++ possono essere modificate.
+myString.append(" Mario");
+cout << myString; // "Ciao Mario"
+
+
+///////////////
+// Riferimenti
+//////////////
+
+// Oltre ai puntatori come quelli in C,
+// il C++ ha i _riferimenti_.
+// Questi non sono tipi puntatori che non possono essere riassegnati una volta settati
+// e non possono essere null.
+// Inoltre, essi hanno la stessa sintassi della variabile stessa:
+// * non è necessario per la dereferenziazione e
+// & ("indirizzo di") non è usato per l'assegnamento.
+
+using namespace std;
+
+string foo = "Io sono foo";
+string bar = "Io sono bar";
+
+
+string& fooRef = foo; // Questo crea un riferimento a foo.
+fooRef += ". Ciao!"; // Modifica foo attraverso il riferimento
+cout << fooRef; // Stampa "Io sono foo. Ciao!"
+
+// Non riassegna "fooRef". Questo è come scrivere "foo = bar", e
+//   foo == "Io sono bar"
+// dopo questa riga.
+fooRef = bar;
+
+const string& barRef = bar; // Crea un riferimento const a bar.
+// Come in C, i valori const (i puntatori e i riferimenti) non possono essere modificati.
+barRef += ". Ciao!"; // Errore, i riferimenti const non possono essere modificati.
+
+//////////////////////////////////////////////////
+// Classi e programmazione orientata agli oggetti
+/////////////////////////////////////////////////
+
+// Primo esempio delle classi
+#include <iostream>
+
+// Dichiara una classe.
+// Le classi sono in genere dichiara in un header file (.h o .hpp).
+class Cane {
+    // Variabili e funzioni membro sono private di default.
+    std::string nome;
+    int peso;
+
+// Tutti i membri dopo questo sono pubblici (public)
+// finchè "private:" o "protected:" non compaiono.
+public:
+
+    // Costruttore di default
+    Cane();
+
+    // Dichiarazioni di funzioni membro (le implentazioni sono a seguito)
+    // Nota che stiamo usando std::string invece di porre
+    // using namespace std;
+    // sopra.
+    // Mai usare uno statement "using namespace" in uno header.
+    void impostaNome(const std::string& nomeCane);
+
+    void impostaPeso(int pesoCane);
+
+    // Le funzioni che non modificano lo stato dell'oggetto
+    // dovrebbero essere marcate come const.
+    // Questo permette di chiamarle con un riferimento const all'oggetto.
+    // Inoltre, nota che le funzioni devono essere dichiarate espliciamente come _virtual_
+    // per essere sovrascritte in classi derivate.
+    // Le funzioni non sono virtual di default per motivi di performance.
+    virtual void print() const;
+
+    // Le funzioni possono essere definite anche all'interno del corpo della classe.
+    // Le funzioni definite in questo modo sono automaticamente inline.
+    void abbaia() const { std::cout << nome << " abbaia!\n"; }
+
+    // Assieme con i costruttori, il C++ fornisce i distruttori.
+    // Questi sono chiamati quando un oggetto è rimosso o esce dalla visibilità.
+    // Questo permette paradigmi potenti come il RAII
+    // (vedi sotto)
+    // I distruttori devono essere virtual per permettere a classi di essere derivate da questa.
+    virtual ~Dog();
+
+}; // Un punto e virgola deve seguire la definizione della funzione
+
+// Le funzioni membro di una classe sono generalmente implementate in files .cpp .
+void Cane::Cane()
+{
+    std::cout << "Un cane è stato costruito\n";
+}
+
+// Gli oggetti (ad esempio le stringhe) devono essere passati per riferimento
+// se li stai modificando o come riferimento const altrimenti.
+void Cane::impostaNome(const std::string& nomeCane)
+{
+    nome = nomeCane;
+}
+
+void Cane::impostaPeso(int pesoCane)
+{
+    peso = pesoCane;
+}
+
+// Notare che "virtual" è solamente necessario nelle dichiarazioni, non nelle definizioni.
+void Cane::print() const
+{
+    std::cout << "Il cane è " << nome << " e pesa " << peso << "kg\n";
+}
+
+void Cane::~Cane()
+{
+    cout << "Ciao ciao " << nome << "\n";
+}
+
+int main() {
+    Cane myDog; // stampa "Un cane è stato costruito"
+    myDog.impostaNome("Barkley");
+    myDog.impostaPeso(10);
+    myDog.print(); // stampa "Il cane è Barkley e pesa 10 kg"
+    return 0;
+} // stampa "Ciao ciao Barkley"
+
+// Ereditarietà:
+
+// Questa classe eredita tutto ciò che è public e protected dalla classe Cane
+class MioCane : public Cane {
+
+    void impostaProprietario(const std::string& proprietarioCane)
+
+    // Sovrascrivi il comportamento della funzione print per tutti i MioCane. Vedi
+    // http://it.wikipedia.org/wiki/Polimorfismo_%28informatica%29
+    // per una introduzione più generale se non sei familiare con
+    // il polimorfismo.
+    // La parola chiave override è opzionale ma fa sì che tu stia effettivamente
+    // sovrascrivendo il metodo nella classe base.
+    void print() const override;
+
+private:
+    std::string proprietario;
+};
+
+// Nel frattempo, nel file .cpp corrispondente:
+
+void MioCane::impostaProprietario(const std::string& proprietarioCane)
+{
+    proprietario = proprietarioCane;
+}
+
+void MioCane::print() const
+{
+    Cane::print(); // Chiama la funzione print nella classe base Cane
+    std::cout << "Il cane è di " << proprietario << "\n";
+    // stampa "Il cane è <nome> e pesa <peso>"
+    //        "Il cane è di <proprietario>"
+}
+
+///////////////////////////////////////////////////
+// Inizializzazione ed Overloading degli Operatori
+//////////////////////////////////////////////////
+
+// In C++ puoi sovrascrivere il comportamento di operatori come +, -, *, /, ecc...
+// Questo è possibile definendo una funzione che viene chiamata
+// ogniqualvolta l'operatore è usato.
+
+#include <iostream>
+using namespace std;
+
+class Punto {
+public:
+    // Così si assegna alle variabili membro un valore di default.
+    double x = 0;
+    double y = 0;
+
+    // Definisce un costruttore di default che non fa nulla
+    // ma inizializza il Punto ai valori di default (0, 0)
+    Punto() { };
+
+    // La sintassi seguente è nota come lista di inizializzazione
+    // ed è il modo appropriato di inizializzare i valori membro della classe
+    Punto (double a, double b) :
+        x(a),
+        y(b)
+    { /* Non fa nulla eccetto inizializzare i valori */ }
+
+    // Sovrascrivi l'operatore +.
+    Punto operator+(const Punto& rhs) const;
+
+    // Sovrascrivi l'operatore +=
+    Punto& operator+=(const Punto& rhs);
+
+    // Avrebbe senso aggiungere gli operatori - e -=,
+    // ma li saltiamo per rendere la guida più breve.
+};
+
+Punto Punto::operator+(const Punto& rhs) const
+{
+    // Crea un nuovo punto come somma di questo e di rhs.
+    return Punto(x + rhs.x, y + rhs.y);
+}
+
+Punto& Punto::operator+=(const Punto& rhs)
+{
+    x += rhs.x;
+    y += rhs.y;
+    return *this;
+}
+
+int main () {
+    Punto su (0,1);
+    Punto destro (1,0);
+    // Questo chiama l'operatore + di Punto
+    // Il Punto su chiama la funzione + con destro come argomento
+    Punto risultato = su + destro;
+    // Stampa "Risultato è spostato in (1,1)"
+    cout << "Risultato è spostato (" << risultato.x << ',' << risultato.y << ")\n";
+    return 0;
+}
+
+/////////////////
+// Templates
+////////////////
+
+// Generalmente i templates in C++ sono utilizzati per programmazione generica, anche se
+// sono molto più potenti dei costrutti generici in altri linguaggi. Inoltre,
+// supportano specializzazione esplicita e parziale, classi in stile funzionale,
+// e sono anche complete per Turing.
+
+// Iniziamo con il tipo di programmazione generica con cui forse sei familiare. Per
+// definire una classe o una funzione che prende un parametro di un dato tipo:
+template<class T>
+class Box {
+    // In questa classe, T può essere usato come qualsiasi tipo.
+    void inserisci(const T&) { ... }
+};
+
+// Durante la compilazione, il compilatore in effetti genera copie di ogni template
+// con i parametri sostituiti, e così la definizione completa della classe deve essere
+// presente ad ogni invocazione. Questo è il motivo per cui vedrai le classi template definite
+// interamente in header files.
+
+// Per instanziare una classe template sullo stack:
+Box<int> intBox;
+
+// e puoi usarla come aspettato:
+intBox.inserisci(123);
+
+//Puoi, ovviamente, innestare i templates:
+Box<Box<int> > boxOfBox;
+boxOfBox.inserisci(intBox);
+
+// Fino al C++11, devi porre uno spazio tra le due '>', altrimenti '>>'
+// viene visto come l'operatore di shift destro.
+
+// Qualche volta vedrai
+// template<typename T>
+// invece. La parole chiavi 'class' e 'typename' sono _generalmente_
+// intercambiabili in questo caso. Per una spiegazione completa, vedi
+// http://en.wikipedia.org/wiki/Typename
+// (si, quella parola chiave ha una sua pagina di Wikipedia propria).
+
+// Similmente, una funzione template:
+template<class T>
+void abbaiaTreVolte(const T& input)
+{
+    input.abbaia();
+    input.abbaia();
+    input.abbaia();
+}
+
+// Nota che niente è specificato relativamente al tipo di parametri. Il compilatore
+// genererà  e poi verificherà il tipo di ogni invocazione del template, così che
+// la funzione di cui sopra funzione con ogni tipo 'T' che ha const 'abbaia' come metodo!
+
+Cane fluffy;
+fluffy.impostaNome("Fluffy")
+abbaiaTreVolte(fluffy); // Stampa "Fluffy abbaia" tre volte.
+
+// I parametri template non devono essere classi:
+template<int Y>
+void stampaMessaggio() {
+  cout << "Impara il C++ in " << Y << " minuti!" << endl;
+}
+
+// E poi esplicitamente specializzare i template per avere codice più efficiente. Ovviamente,
+// la maggior parte delle casistiche reali non sono così triviali.
+// Notare che avrai comunque bisogna di dichiarare la funzione (o classe) come un template
+// anche se hai esplicitamente specificato tutti i parametri.
+template<>
+void stampaMessaggio<10>() {
+  cout << "Impara il C++ più velocemente in soli 10 minuti!" << endl;
+}
+
+printMessage<20>();  // Stampa "impara il C++ in 20 minuti!"
+printMessage<10>();  // Stampa "Impara il C++ più velocemente in soli 10 minuti!"                                   
+                                        
+////////////////////////////
+// Gestione delle eccezioni
+///////////////////////////
+
+// La libreria standard fornisce un paio di tipi d'eccezioni
+// (vedi http://en.cppreference.com/w/cpp/error/exception)
+// ma ogni tipo può essere lanciato come eccezione
+#include <exception>
+
+// Tutte le eccezioni lanciate all'interno del blocco _try_ possono essere catturate dai successivi 
+// handlers _catch_.
+try {
+    // Non allocare eccezioni nello heap usando _new_.
+    throw std::exception("È avvenuto un problema");
+}
+// Cattura le eccezioni come riferimenti const se sono oggetti
+catch (const std::exception& ex)
+{
+  std::cout << ex.what();
+// Cattura ogni eccezioni non catturata dal blocco _catch_ precedente
+} catch (...)
+{
+    std::cout << "Catturata un'eccezione sconosciuta";
+    throw; // Rilancia l'eccezione
+}
+
+///////
+// RAII
+///////
+
+// RAII sta per Resource Allocation Is Initialization.
+// Spesso viene considerato come il più potente paradigma in C++.
+// È un concetto semplice: un costruttore di un oggetto
+// acquisisce le risorse di tale oggetto ed il distruttore le rilascia.
+
+// Per comprendere come questo sia vantaggioso,
+// consideriamo una funzione che usa un gestore di file in C:
+void faiQualcosaConUnFile(const char* nomefile)
+{
+    // Per cominciare, assumiamo che niente possa fallire.
+
+    FILE* fh = fopen(nomefile, "r"); // Apri il file in modalità lettura.
+
+    faiQualcosaConIlFile(fh);
+    faiQualcosAltroConEsso(fh);
+
+    fclose(fh); // Chiudi il gestore di file.
+}
+
+// Sfortunatamente, le cose vengono complicate dalla gestione degli errori.
+// Supponiamo che fopen fallisca, e che faiQualcosaConUnFile e
+// faiQualcosAltroConEsso ritornano codici d'errore se falliscono.
+// (Le eccezioni sono la maniera preferita per gestire i fallimenti,
+//  ma alcuni programmatori, specialmente quelli con un passato in C,
+//  non sono d'accordo con l'utilità delle eccezioni).
+// Adesso dobbiamo verificare che ogni chiamata per eventuali fallimenti e chiudere il gestore di file
+// se un problema è avvenuto.
+bool faiQualcosaConUnFile(const char* nomefile)
+{
+    FILE* fh = fopen(nomefile, "r"); // Apre il file in modalità lettura
+    if (fh == nullptr) // Il puntatore restituito è null in caso di fallimento.
+        return false; // Riporta il fallimento al chiamante.
+
+    // Assumiamo che ogni funzione ritorni false se ha fallito
+    if (!faiQualcosaConIlFile(fh)) {
+        fclose(fh); // Chiude il gestore di file così che non sprechi memoria.
+        return false; // Propaga l'errore.
+    }
+    if (!faiQualcosAltroConEsso(fh)) {
+        fclose(fh); // Chiude il gestore di file così che non sprechi memoria.
+        return false; // Propaga l'errore.
+    }
+
+    fclose(fh); // Chiudi il gestore di file così che non sprechi memoria.
+    return true; // Indica successo
+}
+
+// I programmatori C in genere puliscono questa procedura usando goto:
+bool faiQualcosaConUnFile(const char* nomefile)
+{
+    FILE* fh = fopen(nomefile, "r");
+    if (fh == nullptr)
+        return false;
+
+    if (!faiQualcosaConIlFile(fh))
+        goto fallimento;
+
+    if (!faiQualcosAltroConEsso(fh))
+        goto fallimento;
+
+    fclose(fh); // Chiude il file
+    return true; // Indica successo
+
+fallimento:
+    fclose(fh);
+    return false; // Propaga l'errore
+}
+
+// Se le funzioni indicano errori usando le eccezioni,
+// le cose sono un pò più pulite, ma sono sempre sub-ottimali.
+void faiQualcosaConUnFile(const char* nomefile)
+{
+    FILE* fh = fopen(nomefile, "r"); // Apre il file in modalità lettura
+    if (fh == nullptr)
+        throw std::exception("Non è stato possibile aprire il file.").
+
+    try {
+        faiQualcosaConIlFile(fh);
+        faiQualcosAltroConEsso(fh);
+    }
+    catch (...) {
+        fclose(fh); // Fai sì che il file venga chiuso se si ha un errore.
+        throw; // Poi rilancia l'eccezione.
+    }
+
+    fclose(fh); // Chiudi il file
+    // Tutto è andato bene
+}
+
+// Confronta questo con l'utilizzo della classe C++ file stream (fstream)
+// fstream usa i distruttori per chiudere il file.
+// Come detto sopra, i distruttori sono automaticamente chiamati
+// ogniqualvolta un oggetto esce dalla visibilità.
+void faiQualcosaConUnFile(const std::string& nomefile)
+{
+    // ifstream è l'abbreviazione di input file stream
+    std::ifstream fh(nomefile); // Apre il file
+
+    // Fai qualcosa con il file
+    faiQualcosaConIlFile(fh);
+    faiQualcosAltroConEsso(fh);
+
+} // Il file viene chiuso automaticamente chiuso qui dal distruttore
+
+// Questo ha vantaggi _enormi_:
+// 1. Può succedere di tutto ma
+//    la risorsa (in questo caso il file handler) verrà ripulito.
+//    Una volta che scrivi il distruttore correttamente,
+//    È _impossibile_ scordarsi di chiudere l'handler e sprecare memoria.
+// 2. Nota che il codice è molto più pulito.
+//    Il distruttore gestisce la chiusura del file dietro le scene
+//    senza che tu debba preoccupartene.
+// 3. Il codice è sicuro da eccezioni.
+//    Una eccezione può essere lanciata in qualunque punto nella funzione e la ripulitura
+//    avverrà lo stesso.
+
+// Tutto il codice C++ idiomatico usa RAII in maniera vasta su tutte le risorse.
+// Esempi aggiuntivi includono
+// - Utilizzo della memoria con unique_ptr e shared_ptr
+// - I contenitori - la lista della libreria standard,
+//   vettori (i.e. array auto-aggiustati), mappe hash, e così via
+//   sono tutti automaticamente distrutti con i loro contenuti quando escono dalla visibilità.
+// - I mutex usano lock_guard e unique_lock
+
+///////////////////////
+// Roba divertente
+//////////////////////
+
+// Aspetti del C++ che potrebbero sbalordire i nuovi arrivati (e anche qualche veterano).
+// Questa sezione è, sfortunatamente, selvaggiamente incompleta; il C++ è uno dei linguaggi
+// più facili con cui puoi spararti da solo nel piede.
+
+// Puoi sovrascrivere metodi privati!
+class Foo {
+  virtual void bar();
+};
+class FooSub : public Foo {
+  virtual void bar();  // sovrascrive Foo::bar!
+};
+
+
+// 0 == false == NULL (la maggior parte delle volte)!
+bool* pt = new bool;
+*pt = 0;  // Setta il valore puntato da 'pt' come falso.
+pt = 0;  // Setta 'pt' al puntatore null. Entrambe le righe vengono compilate senza warnings.
+
+// nullptr dovrebbe risolvere alcune di quei problemi:
+int* pt2 = new int;
+*pt2 = nullptr;  // Non compila
+pt2 = nullptr;  // Setta pt2 a null.
+
+// Ma in qualche modo il tipo 'bool' è una eccezione (questo è per rendere compilabile `if (ptr)`.
+*pt = nullptr;  // Questo compila, anche se '*pt' è un bool! 
+
+
+// '=' != '=' != '='!
+// Chiama Foo::Foo(const Foo&) o qualche variante del costruttore di copia.
+Foo f2;
+Foo f1 = f2;
+
+// Chiama Foo::Foo(const Foo&) o qualche variante, ma solo copie di 'Foo' che fanno parte di
+// 'fooSub'. Ogni altro membro di 'fooSub' viene scartato. Questo comportamento
+// orribile viene chiamato "object slicing."
+FooSub fooSub;
+Foo f1 = fooSub;
+
+// Chiama Foo::operator=(Foo&) o una sua variante.
+Foo f1;
+f1 = f2;
+
+```
+Letture consigliate:
+
+Un riferimento aggiornato del linguaggio può essere trovato qui
+<http://cppreference.com/w/cpp>
+
+Risorse addizionali possono essere trovate qui <http://cplusplus.com>

it-it/json-it.html.markdown

@@ -0,0 +1,62 @@
+---
+
+language: json
+contributors:
+  	- ["Anna Harren", "https://github.com/iirelu"]
+  	- ["Marco Scannadinari", "https://github.com/marcoms"]
+translators:
+    - ["Robert Margelli", "http://github.com/sinkswim/"]
+lang: it-it
+
+---
+
+Dato che JSON è un formato per lo scambio di dati estremamente semplice, questo sarà con molta probabilità
+il più semplice Learn X in Y Minutes.
+
+Nella sua forma più pura JSON non ha commenti, ma molti parser accettano
+commenti in stile C (//, /\* \*/). Per lo scopo prefissato, tuttavia, tutto sarà
+100% JSON valido. Fortunatamente, si spiega da sè.
+
+```json
+{
+  "chiave": "valore",
+  
+  "chiavi": "devono sempre essere racchiuse tra doppi apici",
+  "numeri": 0,
+  "stringhe": "Ciaø, møndø. Tutti gli unicode sono permessi, assieme con l \"escaping\".",
+  "ha booleani?": true,
+  "il nulla": null,
+
+  "numero grande": 1.2e+100,
+
+  "oggetti": {
+    "commento": "La maggior parte della tua struttura viene dagli oggetti.",
+
+    "array": [0, 1, 2, 3, "Gli array possono contenere qualsiasi cosa.", 5],
+
+    "un altro oggetto": {
+      "commento": "Queste cose possono essere annidate, molto utile."
+    }
+  },
+
+  "sciocchezze": [
+    {
+      "sorgenti di potassio": ["banane"]
+    },
+    [
+      [1, 0, 0, 0],
+      [0, 1, 0, 0],
+      [0, 0, 1, "neo"],
+      [0, 0, 0, 1]
+    ]
+  ],
+  
+  "stile alternativo": {
+    "commento": "Guarda quà!"
+  , "posizione della virgola": "non conta - fintantochè è prima del valore, allora è valida"
+  , "un altro commento": "che bello"
+  },
+
+  "è stato molto breve": "Ed hai finito. Adesso sai tutto cio che JSON ha da offrire."
+}
+```

java.html.markdown

@@ -1,16 +1,16 @@
 ---
-
 language: java
 contributors:
     - ["Jake Prather", "http://github.com/JakeHP"]
-    - ["Madison Dickson", "http://github.com/mix3d"]
     - ["Jakukyo Friel", "http://weakish.github.io"]
+    - ["Madison Dickson", "http://github.com/mix3d"]
+    - ["Simon Morgan", "http://sjm.io/"]
 filename: LearnJava.java
-
 ---
 
-Java is a general-purpose, concurrent, class-based, object-oriented computer programming language.
+Java is a general-purpose, concurrent, class-based, object-oriented computer
-[Read more here.](http://docs.oracle.com/javase/tutorial/java/index.html)
+programming language.
+[Read more here.](http://docs.oracle.com/javase/tutorial/java/)
 
 ```java
 // Single-line comments start with //
@@ -31,17 +31,17 @@ import java.security.*;
 // the file.
 public class LearnJava {
 
-    // A program must have a main method as an entry point
+    // A program must have a main method as an entry point.
     public static void main (String[] args) {
 
-        // Use System.out.println to print lines
+        // Use System.out.println() to print lines.
         System.out.println("Hello World!");
         System.out.println(
             "Integer: " + 10 +
             " Double: " + 3.14 +
             " Boolean: " + true);
 
-        // To print without a newline, use System.out.print
+        // To print without a newline, use System.out.print().
         System.out.print("Hello ");
         System.out.print("World");
 
@@ -69,7 +69,7 @@ public class LearnJava {
         // L is used to denote that this variable value is of type Long;
         // anything without is treated as integer by default.
 
-        // Note: Java has no unsigned types
+        // Note: Java has no unsigned types.
 
         // Float - Single-precision 32-bit IEEE 754 Floating Point
         float fooFloat = 234.5f;
@@ -86,7 +86,7 @@ public class LearnJava {
         // Char - A single 16-bit Unicode character
         char fooChar = 'A';
 
-        // final variables can't be reassigned to another object
+        // final variables can't be reassigned to another object.
         final int HOURS_I_WORK_PER_WEEK = 9001;
 
         // Strings
@@ -101,10 +101,10 @@ public class LearnJava {
         System.out.println(bazString);
 
         // Arrays
-        //The array size must be decided upon instantiation
+        // The array size must be decided upon instantiation
-        //The following formats work for declaring an array
+        // The following formats work for declaring an array
-        //<datatype>[] <var name> = new <datatype>[<array size>];
+        // <datatype>[] <var name> = new <datatype>[<array size>];
-        //<datatype> <var name>[] = new <datatype>[<array size>];
+        // <datatype> <var name>[] = new <datatype>[<array size>];
         int[] intArray = new int[10];
         String[] stringArray = new String[1];
         boolean boolArray[] = new boolean[100];
@@ -122,17 +122,17 @@ public class LearnJava {
         System.out.println("intArray @ 1: " + intArray[1]); // => 1
 
         // Others to check out
-        // ArrayLists - Like arrays except more functionality is offered,
+        // ArrayLists - Like arrays except more functionality is offered, and
-        //             and the size is mutable
+        //              the size is mutable.
         // LinkedLists - Implementation of doubly-linked list. All of the
-        //             operations perform as could be expected for
+        //               operations perform as could be expected for a
-        //             a doubly-linked list.
+        //               doubly-linked list.
-        // Maps - A set of objects that maps keys to values. A map cannot contain
+        // Maps - A set of objects that maps keys to values. A map cannot
-        //             duplicate keys; each key can map to at most one value.
+        //        contain duplicate keys; each key can map to at most one value.
-        // HashMaps - This class uses a hashtable to implement the Map interface.
+        // HashMaps - This class uses a hashtable to implement the Map
-        //             This allows the execution time of basic operations,
+        //            interface. This allows the execution time of basic
-        //             such as get and insert element, to remain constant even
+        //            operations, such as get and insert element, to remain
-        //             for large sets. 
+        //            constant even for large sets.
 
         ///////////////////////////////////////
         // Operators
@@ -160,13 +160,13 @@ public class LearnJava {
 
         // Bitwise operators!
         /*
-        ~       Unary bitwise complement
+        ~      Unary bitwise complement
-        <<      Signed left shift
+        <<     Signed left shift
-        >>      Signed right shift
+        >>     Signed right shift
-        >>>     Unsigned right shift
+        >>>    Unsigned right shift
-        &       Bitwise AND
+        &      Bitwise AND
-        ^       Bitwise exclusive OR
+        ^      Bitwise exclusive OR
-        |       Bitwise inclusive OR
+        |      Bitwise inclusive OR
         */
 
         // Incrementations
@@ -175,10 +175,10 @@ public class LearnJava {
         // The ++ and -- operators increment and decrement by 1 respectively.
         // If they are placed before the variable, they increment then return;
         // after the variable they return then increment.
-        System.out.println(i++); //i = 1, prints 0 (post-increment)
+        System.out.println(i++); // i = 1, prints 0 (post-increment)
-        System.out.println(++i); //i = 2, prints 2 (pre-increment)
+        System.out.println(++i); // i = 2, prints 2 (pre-increment)
-        System.out.println(i--); //i = 1, prints 2 (post-decrement)
+        System.out.println(i--); // i = 1, prints 2 (post-decrement)
-        System.out.println(--i); //i = 0, prints 0 (pre-decrement)
+        System.out.println(--i); // i = 0, prints 0 (pre-decrement)
 
         ///////////////////////////////////////
         // Control Structures
@@ -197,73 +197,69 @@ public class LearnJava {
 
         // While loop
         int fooWhile = 0;
-        while(fooWhile < 100)
+        while(fooWhile < 100) {
-        {
+            System.out.println(fooWhile);
-            //System.out.println(fooWhile);
+            // Increment the counter
-            //Increment the counter
+            // Iterated 100 times, fooWhile 0,1,2...99
-            //Iterated 100 times, fooWhile 0,1,2...99
             fooWhile++;
         }
         System.out.println("fooWhile Value: " + fooWhile);
 
         // Do While Loop
         int fooDoWhile = 0;
-        do
+        do {
-        {
+            System.out.println(fooDoWhile);
-            //System.out.println(fooDoWhile);
+            // Increment the counter
-            //Increment the counter
+            // Iterated 99 times, fooDoWhile 0->99
-            //Iterated 99 times, fooDoWhile 0->99
             fooDoWhile++;
-        }while(fooDoWhile < 100);
+        } while(fooDoWhile < 100);
         System.out.println("fooDoWhile Value: " + fooDoWhile);
 
         // For Loop
         int fooFor;
-        //for loop structure => for(<start_statement>; <conditional>; <step>)
+        // for loop structure => for(<start_statement>; <conditional>; <step>)
-        for(fooFor=0; fooFor<10; fooFor++){
+        for (fooFor = 0; fooFor < 10; fooFor++) {
-            //System.out.println(fooFor);
+            System.out.println(fooFor);
-            //Iterated 10 times, fooFor 0->9
+            // Iterated 10 times, fooFor 0->9
         }
         System.out.println("fooFor Value: " + fooFor);
 
         // For Each Loop
-        // An automatic iteration through an array or list of objects.
+        // The for loop is also able to iterate over arrays as well as objects
-        int[] fooList = {1,2,3,4,5,6,7,8,9};
+        // that implement the Iterable interface.
-        //for each loop structure => for(<object> : <array_object>)
+        int[] fooList = {1, 2, 3, 4, 5, 6, 7, 8, 9};
-        //reads as: for each object in the array
+        // for each loop structure => for (<object> : <iterable>)
-        //note: the object type must match the array.
+        // reads as: for each element in the iterable
+        // note: the object type must match the element type of the iterable.
 
-        for( int bar : fooList ){
+        for (int bar : fooList) {
-            //System.out.println(bar);
+            System.out.println(bar);
             //Iterates 9 times and prints 1-9 on new lines
         }
 
         // Switch Case
         // A switch works with the byte, short, char, and int data types.
-        // It also works with enumerated types (discussed in Enum Types),
+        // It also works with enumerated types (discussed in Enum Types), the
-        // the String class, and a few special classes that wrap
+        // String class, and a few special classes that wrap primitive types:
-        // primitive types: Character, Byte, Short, and Integer.
+        // Character, Byte, Short, and Integer.
         int month = 3;
         String monthString;
-        switch (month){
+        switch (month) {
-            case 1:
+            case 1: monthString = "January";
-                    monthString = "January";
                     break;
-            case 2:
+            case 2: monthString = "February";
-                    monthString = "February";
                     break;
-            case 3:
+            case 3: monthString = "March";
-                    monthString = "March";
-                    break;
-            default:
-                    monthString = "Some other month";
                     break;
+            default: monthString = "Some other month";
+                     break;
         }
         System.out.println("Switch Case Result: " + monthString);
 
         // Conditional Shorthand
         // You can use the '?' operator for quick assignments or logic forks.
-        // Reads as "If (statement) is true, use <first value>, otherwise, use <second value>"
+        // Reads as "If (statement) is true, use <first value>, otherwise, use
+        // <second value>"
         int foo = 5;
         String bar = (foo < 10) ? "A" : "B";
         System.out.println(bar); // Prints A, because the statement is true
@@ -287,9 +283,8 @@ public class LearnJava {
         // String
 
         // Typecasting
-        // You can also cast java objects, there's a lot of details and
+        // You can also cast Java objects, there's a lot of details and deals
-        // deals with some more intermediate concepts.
+        // with some more intermediate concepts. Feel free to check it out here:
-        // Feel free to check it out here:
         // http://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html
 
 
@@ -319,9 +314,9 @@ public class LearnJava {
 
 
 // Class Declaration Syntax:
-// <public/private/protected> class <class name>{
+// <public/private/protected> class <class name> {
-//    //data fields, constructors, functions all inside.
+//    // data fields, constructors, functions all inside.
-//    //functions are called as methods in Java.
+//    // functions are called as methods in Java.
 // }
 
 class Bicycle {
@@ -342,7 +337,8 @@ class Bicycle {
     }
 
     // This is a constructor that takes arguments
-    public Bicycle(int startCadence, int startSpeed, int startGear, String name) {
+    public Bicycle(int startCadence, int startSpeed, int startGear,
+        String name) {
         this.gear = startGear;
         this.cadence = startCadence;
         this.speed = startSpeed;
@@ -388,10 +384,8 @@ class Bicycle {
     //Method to display the attribute values of this Object.
     @Override
     public String toString() {
-        return "gear: " + gear +
+        return "gear: " + gear + " cadence: " + cadence + " speed: " + speed +
-                " cadence: " + cadence +
+            " name: " + name;
-                " speed: " + speed +
-                " name: " + name;
     }
 } // end class Bicycle
 
@@ -405,26 +399,26 @@ class PennyFarthing extends Bicycle {
         super(startCadence, startSpeed, 0, "PennyFarthing");
     }
 
-    // You should mark a method you're overriding with an @annotation
+    // You should mark a method you're overriding with an @annotation.
-    // To learn more about what annotations are and their purpose
+    // To learn more about what annotations are and their purpose check this
-    // check this out: http://docs.oracle.com/javase/tutorial/java/annotations/
+    // out: http://docs.oracle.com/javase/tutorial/java/annotations/
     @Override
     public void setGear(int gear) {
         gear = 0;
     }
-
 }
 
-//Interfaces
+// Interfaces
-//Interface declaration syntax
+// Interface declaration syntax
-//<access-level> interface <interface-name> extends <super-interfaces> {
+// <access-level> interface <interface-name> extends <super-interfaces> {
-//		//Constants
+//     // Constants
-//		//Method declarations
+//     // Method declarations
-//}
+// }
 
-//Example - Food:
+// Example - Food:
 public interface Edible {
-	public void eat(); //Any class that implements this interface, must implement this method
+	public void eat(); // Any class that implements this interface, must
+                       // implement this method.
 }
 
 public interface Digestible {
@@ -432,33 +426,31 @@ public interface Digestible {
 }
 
 
-//We can now create a class that implements both of these interfaces
+// We can now create a class that implements both of these interfaces.
 public class Fruit implements Edible, Digestible {
     @Override
 	public void eat() {
-		//...
+		// ...
 	}
 
     @Override
 	public void digest() {
-		//... 
+		// ...
 	}
 }
 
-//In java, you can extend only one class, but you can implement many interfaces.
+// In Java, you can extend only one class, but you can implement many
-//For example:
+// interfaces. For example:
-public class ExampleClass extends ExampleClassParent implements InterfaceOne, InterfaceTwo {
+public class ExampleClass extends ExampleClassParent implements InterfaceOne,
+    InterfaceTwo {
     @Override
 	public void InterfaceOneMethod() {
-
 	}
 
     @Override
 	public void InterfaceTwoMethod() {
-
 	}
 }
-
 ```
 
 ## Further Reading
@@ -500,5 +492,3 @@ The links provided here below are just to get an understanding of the topic, fee
 * [Objects First with Java](http://www.amazon.com/Objects-First-Java-Practical-Introduction/dp/0132492660)
 
 * [Java The Complete Reference](http://www.amazon.com/gp/product/0071606300)
-
-

json.html.markdown

@@ -10,7 +10,7 @@ As JSON is an extremely simple data-interchange format, this is most likely goin
 to be the simplest Learn X in Y Minutes ever.
 
 JSON in its purest form has no actual comments, but most parsers will accept
-C-style (//, /\* \*/) comments. For the purposes of this, however,  everything is
+C-style (`//`, `/* */`) comments. For the purposes of this, however,  everything is
 going to be 100% valid JSON. Luckily, it kind of speaks for itself.
 
 ```json

julia.html.markdown

@@ -8,7 +8,7 @@ filename: learnjulia.jl
 Julia is a new homoiconic functional language focused on technical computing.
 While having the full power of homoiconic macros, first-class functions, and low-level control, Julia is as easy to learn and use as Python.
 
-This is based on the current development version of Julia, as of October 18th, 2013.
+This is based on Julia 0.3.
 
 ```ruby
 
@@ -91,7 +91,7 @@ false
 
 # $ can be used for string interpolation:
 "2 + 2 = $(2 + 2)" # => "2 + 2 = 4"
-# You can put any Julia expression inside the parenthesis.
+# You can put any Julia expression inside the parentheses.
 
 # Another way to format strings is the printf macro.
 @printf "%d is less than %f" 4.5 5.3 # 5 is less than 5.300000
@@ -190,7 +190,7 @@ end
 # inside the julia folder to find these files.
 
 # You can initialize arrays from ranges
-a = [1:5] # => 5-element Int64 Array: [1,2,3,4,5]
+a = [1:5;] # => 5-element Int64 Array: [1,2,3,4,5]
 
 # You can look at ranges with slice syntax.
 a[1:3] # => [1, 2, 3]
@@ -264,7 +264,7 @@ in(("two", 3), filled_dict) # => false
 haskey(filled_dict, "one") # => true
 haskey(filled_dict, 1) # => false
 
-# Trying to look up a non-existant key will raise an error
+# Trying to look up a non-existent key will raise an error
 try
     filled_dict["four"] # => ERROR: key not found: four in getindex at dict.jl:489
 catch e

nim.html.markdown

@@ -155,7 +155,7 @@ var anotherArray = ["Default index", "starts at", "0"]
 
 # More data structures are available, including tables, sets, lists, queues,
 # and crit bit trees.
-# http://nimrod-lang.org/lib.html#collections-and-algorithms
+# http://nim-lang.org/docs/lib.html#collections-and-algorithms
 
 #
 # IO and Control Flow
@@ -174,7 +174,7 @@ else:
 
 # `while`, `if`, `continue`, `break`
 
-import strutils as str # http://nimrod-lang.org/strutils.html
+import strutils as str # http://nim-lang.org/docs/strutils.html
 echo "I'm thinking of a number between 41 and 43. Guess which!"
 let number: int = 42
 var
@@ -263,11 +263,11 @@ performance, and compile-time features.
 
 ## Further Reading
 
-* [Home Page](http://nimrod-lang.org)
+* [Home Page](http://nim-lang.org)
-* [Download](http://nimrod-lang.org/download.html)
+* [Download](http://nim-lang.org/download.html)
-* [Community](http://nimrod-lang.org/community.html)
+* [Community](http://nim-lang.org/community.html)
-* [FAQ](http://nimrod-lang.org/question.html)
+* [FAQ](http://nim-lang.org/question.html)
-* [Documentation](http://nimrod-lang.org/documentation.html)
+* [Documentation](http://nim-lang.org/documentation.html)
-* [Manual](http://nimrod-lang.org/manual.html)
+* [Manual](http://nim-lang.org/docs/manual.html)
-* [Standard Library](http://nimrod-lang.org/lib.html)
+* [Standard Library](http://nim-lang.org/docs/lib.html)
-* [Rosetta Code](http://rosettacode.org/wiki/Category:Nimrod)
+* [Rosetta Code](http://rosettacode.org/wiki/Category:Nim)

perl.html.markdown

@@ -47,9 +47,9 @@ my %fruit_color = ("apple", "red", "banana", "yellow");
 #  You can use whitespace and the "=>" operator to lay them out more nicely:
 
 my %fruit_color = (
-        apple  => "red",
+  apple  => "red",
-        banana => "yellow",
+  banana => "yellow",
-        );
+);
 # Scalars, arrays and hashes are documented more fully in perldata.
 # (perldoc perldata).
 
@@ -60,17 +60,17 @@ my %fruit_color = (
 
 # Perl has most of the usual conditional and looping constructs.
 
-if ( $var ) {
+if ($var) {
-    ...
+  ...
-} elsif ( $var eq 'bar' ) {
+} elsif ($var eq 'bar') {
-    ...
+  ...
 } else {
-    ...
+  ...
 }
 
-unless ( condition ) {
+unless (condition) {
-                   ...
+  ...
-               }
+}
 # This is provided as a more readable version of "if (!condition)"
 
 # the Perlish post-condition way
@@ -78,19 +78,29 @@ print "Yow!" if $zippy;
 print "We have no bananas" unless $bananas;
 
 #  while
-  while ( condition ) {
+while (condition) {
-                   ...
+  ...
-               }
+}
 
 
-# for and foreach
+# for loops and iteration
-for ($i = 0; $i <= $max; $i++) {
+for (my $i = 0; $i < $max; $i++) {
-                   ...
+  print "index is $i";
-               }
+}
 
-foreach (@array) {
+for (my $i = 0; $i < @elements; $i++) {
-                   print "This element is $_\n";
+  print "Current element is " . $elements[$i];
-               }
+}
+
+for my $element (@elements) {
+  print $element;
+}
+
+# implicitly
+
+for (@elements) {
+  print;
+}
 
 
 #### Regular expressions
@@ -129,9 +139,11 @@ my @lines = <$in>;
 # Writing subroutines is easy:
 
 sub logger {
-    my $logmessage = shift;
+  my $logmessage = shift;
-    open my $logfile, ">>", "my.log" or die "Could not open my.log: $!";
+
-    print $logfile $logmessage;
+  open my $logfile, ">>", "my.log" or die "Could not open my.log: $!";
+
+  print $logfile $logmessage;
 }
 
 # Now we can use the subroutine just as any other built-in function:

perl6.html.markdown

@@ -213,7 +213,7 @@ say $x; #=> 52
 # - `if`
 # Before talking about `if`, we need to know which values are "Truthy"
 #  (represent True), and which are "Falsey" (or "Falsy") -- represent False.
-# Only these values are Falsey: (), 0, "0", "", Nil, A type (like `Str` or `Int`),
+# Only these values are Falsey: (), 0, "", Nil, A type (like `Str` or `Int`),
 #  and of course False itself.
 # Every other value is Truthy.
 if True {

php.html.markdown

@@ -60,7 +60,7 @@ $float = 1.2e3;
 $float = 7E-10;
 
 // Delete variable
-unset($int1)
+unset($int1);
 
 // Arithmetic
 $sum        = 1 + 1; // 2

pl-pl/python-pl.html.markdown

@@ -0,0 +1,637 @@
+---
+name: python
+category: language
+language: python
+filename: learnpython-pl.py
+contributors:
+    - ["Louie Dinh", "http://ldinh.ca"]
+    - ["Amin Bandali", "http://aminbandali.com"]
+    - ["Andre Polykanine", "https://github.com/Oire"]
+translators:
+    - ["Dominik Krzemiński", "https://github.com/dokato"]
+lang: pl-pl
+---
+
+Python został opracowany przez Guido Van Rossuma na początku lat 90-tych.
+Obecnie jest jednym z najbardziej popularnych języków programowania.
+Zakochałem się w Pythonie dzięki porządkowi, jaki utrzymywany jest w kodzie.
+To po prostu wykonywalny pseudokod.
+
+Zapraszam do kontaktu. Złapiecie nas na:
+- kontakt polski: raymon92 [at] [google's email service]
+- kontakt angielski: [@louiedinh](http://twitter.com/louiedinh) lub louiedinh [at] [google's email service]
+
+Uwaga: Ten artykuł odnosi się do wersji Pythona 2.7, ale powinien
+działać w wersjach 2.x. Dla wersji 3.x znajdziesz odpowiedni artykuł na stronie głównej.
+
+```python
+# -*- coding: utf-8 -*-
+
+# Pojedyncze komentarze oznaczamy takim symbolem.
+
+""" Wielolinijkowe napisy zapisywane są przy użyciu
+    trzech znaków cudzysłowiu i często
+    wykorzystywane są jako komentarze.
+"""
+
+####################################################
+## 1. Podstawowe typy danych i operatory
+####################################################
+
+# Liczby to liczby
+3  # => 3
+
+# Matematyka jest intuicyjna
+1 + 1  # => 2
+8 - 1  # => 7
+10 * 2  # => 20
+35 / 5  # => 7
+
+# Dzielenie może być kłopotliwe. Poniższe to dzielenie
+# całkowitoliczbowe(int) i wynik jest automatycznie zaokrąglany.
+5 / 2  # => 2
+
+# Aby to naprawić musimy powiedzieć nieco o liczbach zmiennoprzecinkowych.
+2.0     # To liczba zmiennoprzecinkowa, tzw. float
+11.0 / 4.0  # => 2.75 ahhh...znacznie lepiej
+
+# Wynik dzielenia całkowitoliczbowego jest obcinany dla liczb
+# dodatnich i ujemnych.
+5 // 3     # => 1
+5.0 // 3.0 # => 1.0 # działa też na floatach
+-5 // 3  # => -2
+-5.0 // 3.0 # => -2.0
+
+# Operator modulo - wyznaczanie reszty z dzielenia
+7 % 3 # => 1
+
+# Potęgowanie (x do potęgi ytej)
+2**4 # => 16
+
+# Wymuszanie pierwszeństwa w nawiasach
+(1 + 3) * 2  # => 8
+
+# Operacje logiczne
+# Zauważ, że przy "and" i "or" trzeba zwracać uwagę na rozmiar liter
+True and False #=> False  # Fałsz
+False or True #=> True   # Prawda
+
+# Zauważ, że operatorów logicznych można używać z intami
+0 and 2 #=> 0
+-5 or 0 #=> -5
+0 == False #=> True
+2 == True #=> False
+k1 == True #=> True
+
+# aby zanegować użyj "not"
+not True  # => False
+not False  # => True
+
+# Równość ==
+1 == 1  # => True
+2 == 1  # => False
+
+# Nierówność !=
+1 != 1  # => False
+2 != 1  # => True
+
+# Więcej porównań
+1 < 10  # => True
+1 > 10  # => False
+2 <= 2  # => True
+2 >= 2  # => True
+
+# Porównania można układać w łańcuch!
+1 < 2 < 3  # => True
+2 < 3 < 2  # => False
+
+# Napisy (typ string) tworzone są przy użyciu cudzysłowów " lub '
+"Jestem napisem."
+'Ja też jestem napisem.'
+
+# Napisy można dodawać!
+"Witaj " + "świecie!"  # => "Witaj świecie!"
+
+# ... a nawet mnożone
+"Hej" * 3  # => "HejHejHej"
+
+# Napis może być traktowany jako lista znaków
+"To napis"[0]  # => 'T'
+
+# % może być używane do formatowania napisów:
+"%s są %s" % ("napisy", "fajne")
+
+# Jednak nowszym sposobem formatowania jest metoda "format".
+# Ta metoda jest obecnie polecana:
+"{0} są {1}".format("napisy", "fajne")
+# Jeśli nie chce ci się liczyć użyj słów kluczowych.
+"{imie} chce zjeść {jadlo}".format(imie="Bob", jasno="lasagne")
+
+# None jest obiektem
+None  # => None
+
+# Nie używaj "==" w celu porównania obiektów z None
+# Zamiast tego użyj "is"
+"etc" is None  # => False
+None is None  # => True
+
+# Operator 'is' testuje identyczność obiektów. To nie jest zbyt 
+# pożyteczne, gdy działamy tylko na prostych wartościach,
+# ale przydaje się, gdy mamy do czynienia z obiektami.
+
+# None, 0, i pusty napis "" są odpowiednikami logicznego False.
+# Wszystkie inne wartości są True
+bool(0)  # => False
+bool("")  # => False
+
+
+####################################################
+## 2. Zmienne i zbiory danych
+####################################################
+
+# Python ma wyrażenie wypisujące "print" we wszystkich wersjach 2.x, ale
+# zostało usunięte z wersji 3.
+print "Jestem Python. Miło poznać!"
+# Python ma też funkcję "print" dostępną w wersjach 2.7 and 3...
+# ale w 2.7 musisz dodać import (odkomentuj):
+# from __future__ import print_function
+print("Ja też jestem Python! ")
+
+# Nie trzeba deklarować zmiennych przed przypisaniem.
+jakas_zmienna = 5    # Konwencja mówi: używaj małych znaków i podłogi _
+jakas_zmienna  # => 5
+
+# Próba dostępu do niezadeklarowanej zmiennej da błąd.
+# Przejdź do sekcji Obsługa wyjątków po więcej...
+inna_zmienna  # Wyrzuca nazwę błędu
+
+# "if" może być użyte jako wyrażenie
+"huraaa!" if 3 > 2 else 2  # => "huraaa!"
+
+# Listy:
+li = []
+# Możesz zacząć od wypełnionej listy
+inna_li = [4, 5, 6]
+
+# Dodaj na koniec używając "append"
+li.append(1)    # li to teraz [1]
+li.append(2)    # li to teraz [1, 2]
+li.append(4)    # li to teraz [1, 2, 4]
+li.append(3)    # li to teraz [1, 2, 4, 3]
+# Usuwanie z konca da "pop"
+li.pop()        # => 3 a li stanie się [1, 2, 4]
+# Dodajmy ponownie
+li.append(3)    # li to znowu [1, 2, 4, 3].
+
+# Dostęp do list jak do każdej tablicy
+li[0]  # => 1
+# Użyj = aby nadpisać wcześniej wypełnione miejsca w liście
+li[0] = 42
+li[0]  # => 42
+li[0] = 1  # Uwaga: ustawiamy starą wartość
+# Tak podglądamy ostatni element
+li[-1]  # => 3
+
+# Jeżeli wyjdziesz poza zakres...
+li[4]  # ... zobaczysz IndexError
+
+# Możesz tworzyć wyniki.
+li[1:3]  # => [2, 4]
+# Bez początku
+li[2:]  # => [4, 3]
+# Omijamy koniec
+li[:3]  # => [1, 2, 4]
+# Wybierz co drugi
+li[::2]   # =>[1, 4]
+# Odwróć listę
+li[::-1]   # => [3, 4, 2, 1]
+# Użyj kombinacji powyższych aby tworzyć bardziej skomplikowane wycinki
+# li[poczatek:koniec:krok]
+
+# Usuń element używając "del"
+del li[2]   # li to teraz [1, 2, 3]
+
+# Listy można dodawać
+li + inna_li   # => [1, 2, 3, 4, 5, 6]
+# Uwaga: wartości poszczególnych list się nie zmieniają.
+
+# Do łączenia list użyj "extend()"
+li.extend(other_li)   # li to teraz [1, 2, 3, 4, 5, 6]
+
+# Sprawdź czy jest w liście używając "in"
+1 in li   # => True
+
+# "len()" pokazuje długość listy
+len(li)   # => 6
+
+
+# Krotki (tuple) są jak listy, ale nie można ich modyfikować.
+tup = (1, 2, 3)
+tup[0]   # => 1
+tup[0] = 3  # wyrzuci TypeError
+
+# Ale wielu akcji dla list możesz używać przy krotkach
+len(tup)   # => 3
+tup + (4, 5, 6)   # => (1, 2, 3, 4, 5, 6)
+tup[:2]   # => (1, 2)
+2 in tup   # => True
+
+# Można rozpakować krotki i listy do poszczególych zmiennych
+a, b, c = (1, 2, 3)     # a to teraz 1, b jest 2, a c to 3
+# Jeżeli zapomnisz nawiasów automatycznie tworzone są krotki
+d, e, f = 4, 5, 6
+# Popatrz jak prosto zamienić wartości
+e, d = d, e     # d to teraz 5 a e to 4
+
+
+# Słowniki są również pożyteczne
+pusty_slownik = {}
+# Tu tworzymy wypełniony:
+pelen_slownik = {"raz": 1, "dwa": 2, "trzy": 3}
+
+# Podglądany wartość
+pelen_slownik["one"]   # => 1
+
+# Wypisz wszystkie klucze używając "keys()"
+pelen_slownik.keys()   # => ["trzy", "dwa", "raz"]
+# Uwaga: słowniki nie gwarantują kolejności występowania kluczy.
+
+# A teraz wszystkie wartości "values()"
+pelen_slownik.values()   # => [3, 2, 1]
+# Uwaga: to samo dotyczy wartości.
+
+# Sprawdzanie czy występuje to "in"
+"raz" in pelen_slownik   # => True
+1 in pelen_slownik   # => False
+
+# Próba dobrania się do nieistniejącego klucza da KeyError
+pelen_slownik["cztery"]   # KeyError
+
+# Użyj "get()" method aby uniknąć KeyError
+pelen_slownik.get("raz")   # => 1
+pelen_slownik.get("cztery")   # => None
+# Metoda get zwraca domyślną wartość gdy brakuje klucza
+pelen_slownik.get("one", 4)   # => 1
+pelen_slownik.get("cztery", 4)   # => 4
+# zauważ, że pelen_slownik.get("cztery") jest wciąż => None
+# (get nie ustawia wartości słownika)
+
+# przypisz wartość do klucza podobnie jak w listach
+pelen_slownik["cztery"] = 4  # teraz: pelen_slownik["cztery"] => 4
+
+# "setdefault()" wstawia do słownika tylko jeśli nie było klucza
+pelen_slownik.setdefault("piec", 5)  # pelen_slownik["piec"] daje 5
+pelen_slownik.setdefault("piec", 6)  # pelen_slownik["piec"] to wciąż 5
+
+
+# Teraz zbiory (set) ... cóż zbiory (to po prostu listy ale bez potórzeń)
+pusty_zbior = set()
+# Inicjalizujemy "set()" pewnymi wartościami
+jakis_zbior = set([1, 2, 2, 3, 4])   # jakis_zbior to teraz set([1, 2, 3, 4])
+
+# kolejność nie jest gwarantowana, nawet gdy wydaje się posortowane
+inny_zbior = set([4, 3, 2, 2, 1])  # inny_zbior to set([1, 2, 3, 4])
+
+# Od Pythona 2.7 nawiasy klamrowe {} mogą być użyte do deklarowania zbioru
+pelen_zbior = {1, 2, 2, 3, 4}   # => {1, 2, 3, 4}
+
+# Dodaj więcej elementów przez "add()"
+pelen_zbior.add(5)   # pelen_zbior is now {1, 2, 3, 4, 5}
+
+# Znajdź przecięcie zbiorów używając &
+inny_zbior = {3, 4, 5, 6}
+pelen_zbior & other_set   # => {3, 4, 5}
+
+# Suma zbiorów |  
+pelen_zbior | other_set   # => {1, 2, 3, 4, 5, 6}
+
+# Różnicę zbiorów da znak -
+{1, 2, 3, 4} - {2, 3, 5}   # => {1, 4}
+
+# Sprawdzanie obecności w zbiorze: "in".
+2 in pelen_zbior   # => True
+10 in pelen_zbior   # => False
+
+
+####################################################
+## 3. Kontrola przepływu
+####################################################
+
+# Tworzymy zmienną some_var
+some_var = 5
+
+# Tutaj widzisz wyrażenie warunkowe "if". Wcięcia są ważne Pythonie! 
+# wypisze "some_var jest mniejsza niż 10"
+if some_var > 10:
+    print("some_var jest wieksza niż 10")
+elif some_var < 10:    # This elif clause is optional.
+    print("some_var jest mniejsza niż 10")
+else:           # This is optional too.
+    print("some_var jest równa 10")
+
+
+"""
+Pętla for iteruje po elementach listy wypisując:
+    pies to ssak
+    kot to ssak
+    mysz to ssak
+"""
+for zwierze in ["pies", "kot", "mysz"]:
+    # Możesz użyć % aby stworzyć sformatowane napisy
+    print("%s to ssak" % zwierze)
+
+"""
+"range(liczba)" zwraca listę liczb
+od zera do danej liczby:
+    0
+    1
+    2
+    3
+"""
+for i in range(4):
+    print(i)
+
+"""
+While to pętla która jest wykonywana dopóki spełniony jest warunek:
+    0
+    1
+    2
+    3
+"""
+x = 0
+while x < 4:
+    print(x)
+    x += 1  # Skrót od x = x + 1
+
+# Wyjątki wyłapujemy używając try, except
+
+# Działa w Pythonie 2.6 i wyższych:
+try:
+    # Użyj "raise" aby wyrzucić wyjąte
+    raise IndexError("To błąd indeksu")
+except IndexError as e:
+    pass    # Pass to brak reakcji na błąd. Zazwyczaj nanosisz tu poprawki.
+except (TypeError, NameError):
+    pass    # kilka wyjątków może być przechwyce razem.
+else:   # Opcjonalna część bloku try/except. Musi wystąpić na końcu
+    print "Wszystko ok!"   # Zadziała tylko, gdy program nie napotka wyjatku.
+
+
+####################################################
+## 4. Funkcjie
+####################################################
+
+# Użyj "def" aby stworzyć nową funkcję
+def dodaj(x, y):
+    print("x to %s a y to %s" % (x, y))
+    return x + y    # słówko kluczowe return zwraca wynik działania
+
+# Tak wywołuje się funkcję z parametrami (args):
+dodaj(5, 6)   # => wypisze "x to 5 a y to 6" i zwróci 11
+
+# Innym sposobem jest wywołanie z parametrami nazwanymi.
+dodaj(y=6, x=5)   # tutaj kolejność podania nie ma znaczenia.
+
+
+# Można też stworzyć funkcję, które przyjmują różną ilość parametrów
+# nienazwanych args, co będzie interpretowane jako krotka jeśli nie użyjesz *
+def varargs(*args):
+    return args
+
+varargs(1, 2, 3)   # => (1, 2, 3)
+
+
+# Można też stworzyć funkcję, które przyjmują różną ilość parametrów
+# nazwanych kwargs, które będa interpretowane jako słownik jeśli nie dasz **
+def keyword_args(**kwargs):
+    return kwargs
+
+# Wywołajmy to i sprawdźmy co się dzieje
+keyword_args(wielka="stopa", loch="ness")   # => {"wielka": "stopa", "loch": "ness"}
+
+
+# Możesz też to pomieszać
+def all_the_args(*args, **kwargs):
+    print(args)
+    print(kwargs)
+"""
+all_the_args(1, 2, a=3, b=4) wyrzuci:
+    (1, 2)
+    {"a": 3, "b": 4}
+"""
+
+# Użyj * aby rozwinąć parametry z krotki args
+# i użyj ** aby rozwinąć parametry nazwane ze słownika kwargs.
+args = (1, 2, 3, 4)
+kwargs = {"a": 3, "b": 4}
+all_the_args(*args)   # odpowiednik foo(1, 2, 3, 4)
+all_the_args(**kwargs)   # odpowiednik foo(a=3, b=4)
+all_the_args(*args, **kwargs)   # odpowiednik foo(1, 2, 3, 4, a=3, b=4)
+
+# Możesz podać parametry args i kwargs do funkcji równocześnie
+# przez rozwinięcie odpowiednio * i **
+def pass_all_the_args(*args, **kwargs):
+    all_the_args(*args, **kwargs)
+    print varargs(*args)
+    print keyword_args(**kwargs)
+
+# Zakres widoczności
+x = 5
+
+def setX(num):
+    # Lokalna zmienna x nie jest tym samym co zmienna x
+    x = num # => 43
+    print x # => 43
+    
+def setGlobalX(num):
+    global x
+    print x # => 5
+    x = num # globalna zmienna to teraz 6
+    print x # => 6
+
+setX(43)
+setGlobalX(6)
+
+# Można tworzyć funkcje wewnętrzne i zwrócić je jako wynik
+def rob_dodawacz(x):
+    def dodawacz(y):
+        return x + y
+    return dodawacz
+
+dodaj_10 = rob_dodawacz(10)
+dodaj_10(3)   # => 13
+
+# Są również funkcje nienazwane "lambda"
+(lambda x: x > 2)(3)   # => True
+
+# Są także wbudowane funkcje wysokiego poziomu
+map(add_10, [1, 2, 3])   # => [11, 12, 13]
+filter(lambda x: x > 5, [3, 4, 5, 6, 7])   # => [6, 7]
+
+# Można używać wyrażeń listowych do mapowania (map) i filtrowania (filter)
+[add_10(i) for i in [1, 2, 3]]  # => [11, 12, 13]
+[x for x in [3, 4, 5, 6, 7] if x > 5]   # => [6, 7]
+
+
+####################################################
+## 5. Klasy
+####################################################
+
+# Wszystkie klasy są podklasą object
+class Czlowiek(object):
+
+    # Atrybut klasy. Występuje we wszystkich instancjach klasy.
+    gatunek = "H. sapiens"
+    
+    # Podstawowa inicjalizacja - wywoływana podczas tworzenia instacji.
+    # Zauważ, że podwójne podkreślenia przed i za nazwą oznaczają
+    # obietky lub atrybuty, który żyją tylko w kontrolowanej przez
+    # użytkownika przestrzeni nazw. Nie używaj ich we własnych metodach.
+    def __init__(self, nazwa):
+        # przypisz parametr "nazwa" do atrybutu instancji
+        self.nazwa = nazwa
+
+    # Metoda instancji. Wszystkie metody biorą "self" jako pierwszy argument
+    def mow(self, wiadomosc):
+        return "%s: %s" % (self.nazwa, wiadomosc)
+
+    # Metoda klasowa współdzielona przez instancje.
+    # Ma wywołującą klasę jako pierwszy argument.
+    @classmethod
+    def daj_gatunek(cls):
+        return cls.gatunek
+
+    # Metoda statyczna jest wywoływana bez argumentów klasy czy instancji.
+    @staticmethod
+    def grunt():
+        return "*grunt*"
+
+
+# Instancja klasy
+i = Czlowiek(name="Ian")
+print(i.mow("cześć"))     # wypisze "Ian: cześć"
+
+j = Czlowiek("Joel")
+print(j.mow("cześć"))  # wypisze "Joel: cześć"
+
+# Wywołujemy naszą metodę klasową
+i.daj_gatunek()   # => "H. sapiens"
+
+# Zmieniamy wspólny parametr
+Czlowiek.gatunek = "H. neanderthalensis"
+i.daj_gatunek()   # => "H. neanderthalensis"
+j.daj_gatunek()   # => "H. neanderthalensis"
+
+# Wywołanie metody statycznej
+Czlowiek.grunt()   # => "*grunt*"
+
+
+####################################################
+## 6. Moduły
+####################################################
+
+# Tak importuje się moduły:
+import math
+print(math.sqrt(16))  # => 4
+
+# Można podać konkretne funkcje, np. ceil, floor z modułu math
+from math import ceil, floor
+print(ceil(3.7))  # => 4.0
+print(floor(3.7))   # => 3.0
+
+# Można zaimportować wszystkie funkcje z danego modułu.
+# Ostrzeżenie: nie jest to polecane.
+from math import *
+
+# Można skracać nazwy modułów.
+import math as m
+math.sqrt(16) == m.sqrt(16)   # => True
+# sprawdźmy czy funkcje są równoważne
+from math import sqrt
+math.sqrt == m.sqrt == sqrt  # => True
+
+# Moduły pythona to zwykłe skrypty napisane w tym języku. Możesz
+# pisać własne i importować je. Nazwa modułu to nazwa pliku.
+
+# W ten sposób sprawdzisz jakie funkcje wchodzą w skład modułu.
+import math
+dir(math)
+
+
+####################################################
+## 7. Zaawansowane
+####################################################
+
+# Generatory pomagają tworzyć tzw. "leniwy kod"
+def podwojne_liczby(iterowalne):
+    for i in iterowalne:
+        yield i + i
+
+# Generatory tworzą wartości w locie.
+# W przeciwienstwie do wygenerowania wartości raz i ich zachowania, 
+# powstają one na bieżąco, w wyniku iteracji. To oznacza, że wartości
+# większe niż 15 nie będą przetworzone w funkcji "podwojne_liczby".
+# Zauważ, że xrange to generator, który wykonuje tę samą operację co range.
+# Stworzenie listy od 1 do 900000000 zajęłoby sporo czasu i pamięci,
+# a xrange tworzy obiekt generatora zamiast tworzyć całą listę jak range.
+# Użyto podkreślinika, aby odróżnić nazwę zmiennej od słówka kluczowego
+# Pythona.
+xrange_ = xrange(1, 900000000)
+
+# poniższa pętla będzie podwajać liczby aż do 30 
+for i in podwojne_liczby(xrange_):
+    print(i)
+    if i >= 30:
+        break
+
+
+# Dekoratory
+# w tym przykładzie "beg" jest nakładką na "say"
+# Beg wywołuje say. Jeśli say_please jest prawdziwe wtedy wzracana wartość
+# zostanie zmieniona
+
+from functools import wraps
+
+
+def beg(target_function):
+    @wraps(target_function)
+    def wrapper(*args, **kwargs):
+        msg, say_please = target_function(*args, **kwargs)
+        if say_please:
+            return "{} {}".format(msg, "Proszę! Jestem spłukany :(")
+        return msg
+    return wrapper
+
+
+@beg
+def say(say_please=False):
+    msg = "Kupisz mi piwo?"
+    return msg, say_please
+
+
+print(say())  # Kupisz mi piwo?
+print(say(say_please=True))  # Kupisz mi piwo? Proszę! Jestem spłukany :(
+```
+
+## Gotowy na więcej?
+### Polskie
+
+* [Zanurkuj w Pythonie](http://pl.wikibooks.org/wiki/Zanurkuj_w_Pythonie)
+* [LearnPythonPl](http://www.learnpython.org/pl/)
+
+### Angielskie:
+#### Darmowe źródła online
+
+* [Learn Python The Hard Way](http://learnpythonthehardway.org/book/)
+* [Dive Into Python](http://www.diveintopython.net/)
+* [The Official Docs](http://docs.python.org/2.6/)
+* [Hitchhiker's Guide to Python](http://docs.python-guide.org/en/latest/)
+* [Python Module of the Week](http://pymotw.com/2/)
+* [A Crash Course in Python for Scientists](http://nbviewer.ipython.org/5920182)
+
+#### Inne
+
+* [Programming Python](http://www.amazon.com/gp/product/0596158106/ref=as_li_qf_sp_asin_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0596158106&linkCode=as2&tag=homebits04-20)
+* [Dive Into Python](http://www.amazon.com/gp/product/1441413022/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=1441413022&linkCode=as2&tag=homebits04-20)
+* [Python Essential Reference](http://www.amazon.com/gp/product/0672329786/ref=as_li_tf_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0672329786&linkCode=as2&tag=homebits04-20)
+

pt-br/groovy-pt.html.markdown

@@ -9,7 +9,7 @@ translators:
 lang: pt-br
 ---
 
-Groovy - Uma linguagem dinâmica para a plataforma Java. [Leia mais aqui.](http://groovy.codehaus.org)
+Groovy - Uma linguagem dinâmica para a plataforma Java. [Leia mais aqui.](http://www.groovy-lang.org/)
 
 ```groovy
 
@@ -236,7 +236,7 @@ for ( e in map ) {
 
   Sobrecarregamento de Operadores para uma lsita dos operadores comuns que
   Grooby suporta:
-  http://groovy.codehaus.org/Operator+Overloading
+  http://www.groovy-lang.org/operators.html#Operator-Overloading
 
   Operadores Groovy úteis
 */
@@ -255,7 +255,7 @@ def nomeUsuario = usuario?.nomeUsuario
   Um closure, em Grooby, é como um "bloco de código" ou um ponteiro para método.
   É um pedação de código que é definido e executado em um momento posterior.
 
-  Mais informação em: http://groovy.codehaus.org/Closures+-+Formal+Definition
+  Mais informação em: http://www.groovy-lang.org/closures.html
 */
 //Exemplo:
 def clos = { println "Hello World!" }
@@ -413,11 +413,11 @@ assert soma(2,5) == 7
 
 ## Referências
 
-[Groovy documentation](http://groovy.codehaus.org/Documentation)
+[Groovy documentation](http://www.groovy-lang.org/documentation.html)
 
 [Groovy web console](http://groovyconsole.appspot.com/)
 
-Junte-se a um [grupo de usuários Groovy](http://groovy.codehaus.org/User+Groups)
+Junte-se a um [grupo de usuários Groovy](http://www.groovy-lang.org/usergroups.html)
 
 ## Livro
 

python.html.markdown

@@ -191,14 +191,14 @@ li[2:]  # => [4, 3]
 li[:3]  # => [1, 2, 4]
 # Select every second entry
 li[::2]   # =>[1, 4]
-# Revert the list
+# Reverse a copy of the list
 li[::-1]   # => [3, 4, 2, 1]
 # Use any combination of these to make advanced slices
 # li[start:end:step]
 
 # Remove arbitrary elements from a list with "del"
 del li[2]   # li is now [1, 2, 3]
-
+r
 # You can add lists
 li + other_li   # => [1, 2, 3, 4, 5, 6]
 # Note: values for li and for other_li are not modified.

python3.html.markdown

@@ -186,7 +186,7 @@ li[2:]  # => [4, 3]
 li[:3]  # => [1, 2, 4]
 # Select every second entry
 li[::2]   # =>[1, 4]
-# Revert the list
+# Return a reversed copy of the list
 li[::-1]   # => [3, 4, 2, 1]
 # Use any combination of these to make advanced slices
 # li[start:end:step]
@@ -213,7 +213,7 @@ tup = (1, 2, 3)
 tup[0]   # => 1
 tup[0] = 3  # Raises a TypeError
 
-# You can do all those list thingies on tuples too
+# You can do most of the list operations on tuples too
 len(tup)   # => 3
 tup + (4, 5, 6)   # => (1, 2, 3, 4, 5, 6)
 tup[:2]   # => (1, 2)
@@ -235,15 +235,15 @@ filled_dict = {"one": 1, "two": 2, "three": 3}
 # Look up values with []
 filled_dict["one"]   # => 1
 
-# Get all keys as a list with "keys()". 
+# Get all keys as an iterable with "keys()". We need to wrap the call in list()
-# We need to wrap the call in list() because we are getting back an iterable. We'll talk about those later.
+# to turn it into a list. We'll talk about those later.  Note - Dictionary key
-# Note - Dictionary key ordering is not guaranteed.
+# ordering is not guaranteed. Your results might not match this exactly.
-# Your results might not match this exactly.
 list(filled_dict.keys())   # => ["three", "two", "one"]
 
 
-# Get all values as a list with "values()". Once again we need to wrap it in list() to get it out of the iterable.
+# Get all values as an iterable with "values()". Once again we need to wrap it
-# Note - Same as above regarding key ordering.
+# in list() to get it out of the iterable. Note - Same as above regarding key
+# ordering.
 list(filled_dict.values())   # => [3, 2, 1]
 
 
@@ -328,7 +328,7 @@ for animal in ["dog", "cat", "mouse"]:
     print("{} is a mammal".format(animal))
 
 """
-"range(number)" returns a list of numbers
+"range(number)" returns an iterable of numbers
 from zero to the given number
 prints:
     0
@@ -340,7 +340,7 @@ for i in range(4):
     print(i)
 
 """
-"range(lower, upper)" returns a list of numbers
+"range(lower, upper)" returns an iterable of numbers
 from the lower number to the upper number
 prints:
     4

ru-ru/bash-ru.html.markdown

@@ -0,0 +1,284 @@
+---
+category: tool
+tool: bash
+contributors:
+    - ["Max Yankov", "https://github.com/golergka"]
+    - ["Darren Lin", "https://github.com/CogBear"]
+    - ["Alexandre Medeiros", "http://alemedeiros.sdf.org"]
+    - ["Denis Arh", "https://github.com/darh"]
+    - ["akirahirose", "https://twitter.com/akirahirose"]
+    - ["Anton Strömkvist", "http://lutic.org/"]
+    - ["Rahil Momin", "https://github.com/iamrahil"]
+    - ["Gregrory Kielian", "https://github.com/gskielian"]
+    - ["Etan Reisner", "https://github.com/deryni"]
+translators:
+    - ["Andrey Samsonov", "https://github.com/kryzhovnik"]
+    - ["Andre Polykanine", "https://github.com/Oire"]
+filename: LearnBash-ru.sh
+lang: ru-ru
+---
+
+Bash - это командная оболочка unix (unix shell), которая распространялась как оболочка для операционной системы GNU и используется в качестве оболочки по умолчанию для Linux и Mac OS X.
+Почти все нижеприведенные примеры могут быть частью shell-скриптов или исполнены напрямую в shell.
+
+[Подробнее.](http://www.gnu.org/software/bash/manual/bashref.html)
+
+```bash
+#!/bin/bash
+# Первая строка скрипта - это shebang, который сообщает системе, как исполнять
+# этот скрипт: http://en.wikipedia.org/wiki/Shebang_(Unix)
+# Как вы уже поняли, комментарии начинаются с #. Shebang - тоже комментарий.
+
+# Простой пример hello world:
+echo Hello world!
+
+# Отдельные команды начинаются с новой строки или разделяются точкой с запятой:
+echo 'Это первая строка'; echo 'Это вторая строка'
+
+# Вот так объявляется переменная:
+VARIABLE="Просто строка"
+
+# но не так:
+VARIABLE = "Просто строка"
+# Bash решит, что VARIABLE - это команда, которую он должен исполнить,
+# и выдаст ошибку, потому что не сможет найти ее.
+
+# и не так:
+VARIABLE= 'Просто строка'
+# Тут Bash решит, что 'Просто строка' - это команда, которую он должен исполнить,
+# и выдаст ошибку, потому что не сможет найти такой команды
+# (здесь 'VARIABLE=' выглядит как присвоение значения переменной,
+# но только в контексте исполнения команды 'Просто строка').
+
+# Использование переменой:
+echo $VARIABLE
+echo "$VARIABLE"
+echo '$VARIABLE'
+# Когда вы используете переменную - присваиваете, экспортируете и т.д. -
+# пишите её имя без $. А для получения значения переменной используйте $.
+# Заметьте, что ' (одинарные кавычки) не раскрывают переменные в них.
+
+# Подстановка строк в переменные
+echo ${VARIABLE/Просто/A}
+# Это выражение заменит первую встреченную подстроку "Просто" на "A"
+
+# Взять подстроку из переменной
+LENGTH=7
+echo ${VARIABLE:0:LENGTH}
+# Это выражение вернет только первые 7 символов переменной VARIABLE
+
+# Значение по умолчанию
+echo ${FOO:-"DefaultValueIfFOOIsMissingOrEmpty"}
+# Это сработает при отсутствующем значении (FOO=) и пустой строке (FOO="");
+# ноль (FOO=0) вернет 0.
+# Заметьте, что в любом случае значение самой переменной FOO не изменится.
+
+# Встроенные переменные:
+# В bash есть полезные встроенные переменные, например
+echo "Последнее возвращенное значение: $?"
+echo "PID скрипта: $$"
+echo "Количество аргументов: $#"
+echo "Аргументы скрипта: $@"
+echo "Аргументы скрипта, распределённые по отдельным переменным: $1 $2..."
+
+# Чтение аргументов из устройста ввода:
+echo "Как Вас зовут?"
+read NAME # Обратите внимание, что нам не нужно определять новую переменную
+echo Привет, $NAME!
+
+# У нас есть обычная структура if:
+# наберите 'man test' для получения подробной информации о форматах условия
+if [ $NAME -ne $USER ]
+then
+    echo "Имя не совпадает с именем пользователя"
+else
+    echo "Имя совпадает с именем пользователя"
+fi
+
+# Также есть условное исполнение
+echo "Исполнится всегда" || echo "Исполнится, если первая команда завершится ошибкой"
+echo "Исполнится всегда" && echo "Исполнится, если первая команда выполнится удачно"
+
+# Можно использовать && и || в выражениях if, когда нужно несколько пар скобок:
+if [ $NAME == "Steve" ] && [ $AGE -eq 15 ]
+then
+    echo "Исполнится, если $NAME равно Steve И $AGE равно 15."
+fi
+
+if [ $NAME == "Daniya" ] || [ $NAME == "Zach" ]
+then
+    echo "Исполнится, если $NAME равно Daniya ИЛИ Zach."
+fi
+
+# Выражения обозначаются таким форматом:
+echo $(( 10 + 5 ))
+
+# В отличие от других языков программирования, Bash - это командная оболочка,
+# а значит, работает в контексте текущей директории.
+# Вы можете просматривать файлы и директории в текущей директории командой ls:
+ls
+
+# У этой команды есть опции:
+ls -l # Показать каждый файл и директорию на отдельной строке
+
+# Результат предыдущей команды может быть направлен на вход следующей.
+# Команда grep фильтрует ввод по шаблону.
+# Так мы можем просмотреть только *.txt файлы в текущей директории:
+ls -l | grep "\.txt"
+
+# Вы можете перенаправить ввод и вывод команды (stdin, stdout и stderr).
+# Следующая команда означает: читать из stdin, пока не встретится ^EOF$, и
+# перезаписать hello.py следующим строками (до строки "EOF"):
+cat > hello.py << EOF
+#!/usr/bin/env python
+from __future__ import print_function
+import sys
+print("#stdout", file=sys.stdout)
+print("#stderr", file=sys.stderr)
+for line in sys.stdin:
+    print(line, file=sys.stdout)
+EOF
+
+# Запуск hello.py с разными вариантами перенаправления потоков
+# стандартных ввода, вывода и ошибок:
+python hello.py < "input.in"
+python hello.py > "output.out"
+python hello.py 2> "error.err"
+python hello.py > "output-and-error.log" 2>&1
+python hello.py > /dev/null 2>&1
+# Поток ошибок перезапишет файл, если этот файл существует,
+# поэтому, если вы хотите дописывать файл, используйте ">>":
+python hello.py >> "output.out" 2>> "error.err"
+
+# Переписать output.txt, дописать error.err и сосчитать строки:
+info bash 'Basic Shell Features' 'Redirections' > output.out 2>> error.err
+wc -l output.out error.err
+
+# Запустить команду и вывести ее файловый дескриптор (смотрите: man fd)
+echo <(echo "#helloworld")
+
+# Перезаписать output.txt строкой "#helloworld":
+cat > output.out <(echo "#helloworld")
+echo "#helloworld" > output.out
+echo "#helloworld" | cat > output.out
+echo "#helloworld" | tee output.out >/dev/null
+
+# Подчистить временные файлы с подробным выводом ('-i' - интерактивый режим)
+rm -v output.out error.err output-and-error.log
+
+# Команды могут быть подставлены в строку с помощью $( ):
+# следующие команды выводят число файлов и директорий в текущей директории.
+echo "Здесь $(ls | wc -l) элементов."
+
+# То же самое можно сделать с использованием обратных кавычек,
+# но они не могут быть вложенными, поэтому предпочтительно использовать $( ).
+echo "Здесь `ls | wc -l` элементов."
+
+# В Bash есть структура case, которая похожа на switch в Java и C++:
+case "$VARIABLE" in 
+    # Перечислите шаблоны для условий, которые хотите отловить
+    0) echo "Тут ноль.";;
+    1) echo "Тут один.";;
+    *) echo "Это не пустое значение.";;
+esac
+
+# Цикл for перебирает элементы переданные в аргументе:
+# Содержимое $VARIABLE будет напечатано три раза.
+for VARIABLE in {1..3}
+do
+    echo "$VARIABLE"
+done
+
+# Или с использованием "традиционного" синтаксиса цикла for:
+for ((a=1; a <= 3; a++))
+do
+    echo $a
+done
+
+# Цикл for можно использовать для действий с файлами.
+# Запустим команду 'cat' для файлов file1 и file2
+for VARIABLE in file1 file2
+do
+    cat "$VARIABLE"
+done
+
+# ... или выводом из команд
+# Запустим cat для вывода из ls.
+for OUTPUT in $(ls)
+do
+    cat "$OUTPUT"
+done
+
+# Цикл while:
+while [ true ]
+do
+    echo "тело цикла здесь..."
+    break
+done
+
+# Вы можете определять функции
+# Определение:
+function foo ()
+{
+    echo "Аргументы работают также, как аргументы скрипта: $@"
+    echo "и: $1 $2..."
+    echo "Это функция"
+    return 0
+}
+
+# или просто
+bar ()
+{
+    echo "Другой способ определить функцию!"
+    return 0
+}
+
+# Вызов функции
+foo "Мое имя" $NAME
+
+# Есть много полезных команд, которые нужно знать:
+# напечатать последние 10 строк файла file.txt
+tail -n 10 file.txt
+# напечатать первые 10 строк файла file.txt
+head -n 10 file.txt
+# отсортировать строки file.txt
+sort file.txt
+# отобрать или наоборот пропустить повторяющиеся строки (с опцией -d отбирает)
+uniq -d file.txt
+# напечатать только первую колонку перед символом ','
+cut -d ',' -f 1 file.txt
+# заменить каждое 'okay' на 'great' в файле file.txt (regex поддерживается)
+sed -i 's/okay/great/g' file.txt
+# вывести в stdout все строки из file.txt, совпадающие с шаблоном regex;
+# этот пример выводит строки, которые начинаются на "foo" и оканчиваются "bar"
+grep "^foo.*bar$" file.txt
+# передайте опцию -c чтобы вывести число строк, в которых совпал шаблон
+grep -c "^foo.*bar$" file.txt
+# чтобы искать по строке, а не шаблону regex, используйте fgrep (или grep -F)
+fgrep "^foo.*bar$" file.txt 
+
+# Читайте встроенную документацию оболочки Bash командой 'help':
+help
+help help
+help for
+help return
+help source
+help .
+
+# Читайте Bash man-документацию
+apropos bash
+man 1 bash
+man bash
+
+# Читайте документацию info (? для помощи)
+apropos info | grep '^info.*('
+man info
+info info
+info 5 info
+
+# Читайте bash info документацию:
+info bash
+info bash 'Bash Features'
+info bash 6
+info --apropos bash
+```

ruby.html.markdown

@@ -79,10 +79,14 @@ true && false #=> false
 true || false #=> true
 !true #=> false
 
-# Alternate spellings of logical operators
+# There are alternate versions of the logical operators with much lower
-true and false #=> false
+# precedence. These are meant to be used as flow-control constructs to chain
-true or false #=> true
+# statements together until one of them returns true or false.
-not true #=> false
+
+# `do_something_else` only called if `do_something` succeeds.
+do_something() and do_something_else()
+# `log_error` only called if `do_something` fails.
+do_something() or log_error()
 
 
 # Strings are objects

rust.html.markdown

@@ -5,15 +5,22 @@ contributors:
 filename: learnrust.rs
 ---
 
-Rust is an in-development programming language developed by Mozilla Research.
+Rust is a programming language developed by Mozilla Research.
-It is relatively unique among systems languages in that it can assert memory
+Rust combines low-level control over performance with high-level convenience and 
-safety *at compile time* without resorting to garbage collection. Rust’s first
+safety guarantees. 
-release, 0.1, occurred in January 2012, and development moves so quickly that at
+
-the moment the use of stable releases is discouraged, and instead one should use
+It achieves these goals without requiring a garbage collector or runtime, making 
-nightly builds. On January 9 2015, Rust 1.0 Alpha was released, and the rate of
+it possible to use Rust libraries as a "drop-in replacement" for C.
-changes to the Rust compiler that break existing code has dropped significantly
+
-since. However, a complete guarantee of backward compatibility will not exist
+Rust’s first release, 0.1, occurred in January 2012, and for 3 years development 
-until the final 1.0 release.
+moved so quickly that until recently the use of stable releases was discouraged
+and instead the general advise was to use nightly builds. 
+
+On May 15th 2015, Rust 1.0 was released with a complete guarantee of backward 
+compatibility. Improvements to compile times and other aspects of the compiler are
+currently available in the nightly builds. Rust has adopted a train-based release
+model with regular releases every six weeks. Rust 1.1 beta was made available at 
+the same time of the release of Rust 1.0.
 
 Although Rust is a relatively low-level language, Rust has some functional
 concepts that are generally found in higher-level languages. This makes
@@ -77,7 +84,7 @@ fn main() {
     // This is basically an immutable pointer to a string – it doesn’t
     // actually contain the contents of a string, just a pointer to
     // something that does (in this case, `s`)
-    let s_slice: &str = &*s;
+    let s_slice: &str = &s;
 
     println!("{} {}", s, s_slice); // hello world hello world
 
@@ -92,7 +99,7 @@ fn main() {
 
     // A slice – an immutable view into a vector or array
     // This is much like a string slice, but for vectors
-    let slice: &[i32] = &*vector;
+    let slice: &[i32] = &vector;
 
     // Use `{:?}` to print something debug-style
     println!("{:?} {:?}", vector, slice); // [1, 2, 3, 4, 5] [1, 2, 3, 4, 5]

standard-ml.html.markdown

@@ -3,13 +3,15 @@ language: "Standard ML"
 contributors:
     - ["Simon Shine", "http://shine.eu.org/"]
     - ["David Pedersen", "http://lonelyproton.com/"]
+    - ["James Baker", "http://www.jbaker.io/"]
+    - ["Leo Zovic", "http://langnostic.inaimathi.ca/"]
 ---
 
 Standard ML is a functional programming language with type inference and some
 side-effects.  Some of the hard parts of learning Standard ML are: Recursion,
 pattern matching, type inference (guessing the right types but never allowing
-implicit type conversion).  If you have an imperative background, not being able
+implicit type conversion). Standard ML is distinguished from Haskell by including
-to update variables can feel severely inhibiting.
+references, allowing variables to be updated.
 
 ```ocaml
 (* Comments in Standard ML begin with (* and end with *).  Comments can be
@@ -135,9 +137,29 @@ val mixup = [ ("Alice", 39),
 
 val good_bad_stuff =
   (["ice cream", "hot dogs", "chocolate"],
-   ["liver", "paying the rent" ])           (* string list * string list *)
+   ["liver", "paying the rent" ])           (* : string list * string list *)
 
 
+(* Records are tuples with named slots *)
+
+val rgb = { r=0.23, g=0.56, b=0.91 } (* : {b:real, g:real, r:real} *)
+
+(* You don't need to declare their slots ahead of time. Records with
+   different slot names are considered different types, even if their
+   slot value types match up. For instance... *)
+
+val Hsl = { H=310.3, s=0.51, l=0.23 } (* : {H:real, l:real, s:real} *)
+val Hsv = { H=310.3, s=0.51, v=0.23 } (* : {H:real, s:real, v:real} *)
+
+(* ...trying to evaluate `Hsv = Hsl` or `rgb = Hsl` would give a type
+   error. While they're all three-slot records composed only of `real`s,
+   they each have different names for at least some slots. *)
+
+(* You can use hash notation to get values out of tuples. *)
+
+val H = #H Hsv (* : real *)
+val s = #s Hsl (* : real *)
+
 (* Functions! *)
 fun add_them (a, b) = a + b    (* A simple function that adds two numbers *)
 val test_it = add_them (3, 4)  (* gives 7 *)
@@ -224,17 +246,26 @@ fun fibonacci 0 = 0  (* Base case *)
   | fibonacci 1 = 1  (* Base case *)
   | fibonacci n = fibonacci (n - 1) + fibonacci (n - 2)  (* Recursive case *)
 
-(* Pattern matching is also possible on composite types like tuples and lists.
+(* Pattern matching is also possible on composite types like tuples, lists and
-   Writing "fun solve2 (a, b, c) = ..." is in fact a pattern match on the one
+   records. Writing "fun solve2 (a, b, c) = ..." is in fact a pattern match on
-   three-tuple solve2 takes as argument. Similarly, but less intuitively, you
+   the one three-tuple solve2 takes as argument. Similarly, but less intuitively,
-   can match on a list consisting of elements in it (from the beginning of the
+   you can match on a list consisting of elements in it (from the beginning of
-   list only). *)
+   the list only). *)
 fun first_elem (x::xs) = x
 fun second_elem (x::y::xs) = y
 fun evenly_positioned_elems (odd::even::xs) = even::evenly_positioned_elems xs
   | evenly_positioned_elems [odd] = []  (* Base case: throw away *)
   | evenly_positioned_elems []    = []  (* Base case *)
 
+(* When matching on records, you must use their slot names, and you must bind
+   every slot in a record. The order of the slots doesn't matter though. *)
+
+fun rgbToTup {r, g, b} = (r, g, b)    (* fn : {b:'a, g:'b, r:'c} -> 'c * 'b * 'a *)
+fun mixRgbToTup {g, b, r} = (r, g, b) (* fn : {b:'a, g:'b, r:'c} -> 'c * 'b * 'a *)
+
+(* If called with {r=0.1, g=0.2, b=0.3}, either of the above functions
+   would return (0.1, 0.2, 0.3). But it would be a type error to call them
+   with {r=0.1, g=0.2, b=0.3, a=0.4} *)
 
 (* Higher order functions: Functions can take other functions as arguments.
    Functions are just other kinds of values, and functions don't need names
@@ -383,6 +414,25 @@ val test_poem = readPoem "roses.txt"  (* gives [ "Roses are red,",
                                                  "Violets are blue.",
                                                  "I have a gun.",
                                                  "Get in the van." ] *)
+
+(* We can create references to data which can be updated *)
+val counter = ref 0 (* Produce a reference with the ref function *)
+
+(* Assign to a reference with the assignment operator *)
+fun set_five reference = reference := 5
+
+(* Read a reference with the dereference operator *)
+fun equals_five reference = !reference = 5
+
+(* We can use while loops for when recursion is messy *)
+fun decrement_to_zero r = if !r < 0
+                          then r := 0
+                          else while !r >= 0 do r := !r - 1
+
+(* This returns the unit value (in practical terms, nothing, a 0-tuple) *)
+
+(* To allow returning a value, we can use the semicolon to sequence evaluations *)
+fun decrement_ret x y = (x := !x - 1; y)
 ```
 
 ## Further learning

visualbasic.html.markdown

@@ -159,7 +159,7 @@ Module Module1
         Console.Write(a.ToString() + " - " + b.ToString())
         Console.WriteLine(" = " + e.ToString.PadLeft(3))
         Console.Write(a.ToString() + " / " + b.ToString())
-        Console.WriteLine(" = " + e.ToString.PadLeft(3))
+        Console.WriteLine(" = " + f.ToString.PadLeft(3))
         Console.ReadLine()
 
     End Sub
@@ -189,7 +189,7 @@ Module Module1
             Console.Write(a.ToString() + " - " + b.ToString())
             Console.WriteLine(" = " + e.ToString.PadLeft(3))
             Console.Write(a.ToString() + " / " + b.ToString())
-            Console.WriteLine(" = " + e.ToString.PadLeft(3))
+            Console.WriteLine(" = " + f.ToString.PadLeft(3))
             Console.ReadLine()
             'Ask the question, does the user wish to continue? Unfortunately it
             'is case sensitive. 

zh-cn/bash-cn.html.markdown

@@ -5,7 +5,14 @@ contributors:
     - ["Max Yankov", "https://github.com/golergka"]
     - ["Darren Lin", "https://github.com/CogBear"]
     - ["Alexandre Medeiros", "http://alemedeiros.sdf.org"]
+    - ["Denis Arh", "https://github.com/darh"]
+    - ["akirahirose", "https://twitter.com/akirahirose"]
+    - ["Anton Strömkvist", "http://lutic.org/"]
+    - ["Rahil Momin", "https://github.com/iamrahil"]
+    - ["Gregrory Kielian", "https://github.com/gskielian"]
+    - ["Etan Reisner", "https://github.com/deryni"]
 translators:
+    - ["Jinchang Ye", "https://github.com/Alwayswithme"]
     - ["Chunyang Xu", "https://github.com/XuChunyang"]
 filename: LearnBash-cn.sh
 lang: zh-cn
@@ -23,31 +30,45 @@ Bash 是一个为 GNU 计划编写的 Unix shell，是 Linux 和 Mac OS X 下的
 # 如你所见，注释以 # 开头，shebang 也是注释。
 
 # 显示 “Hello world!”
-echo Hello, world!
+echo Hello world!
 
 # 每一句指令以换行或分号隔开：
 echo 'This is the first line'; echo 'This is the second line'
 
 # 声明一个变量：
-VARIABLE="Some string"
+Variable="Some string"
 
 # 下面是错误的做法：
-VARIABLE = "Some string"
+Variable = "Some string"
-# Bash 会把 VARIABLE 当做一个指令，由于找不到该指令，因此这里会报错。
+# Bash 会把 Variable 当做一个指令，由于找不到该指令，因此这里会报错。
 
+# 也不可以这样：
+Variable= 'Some string'
+# Bash 会认为 'Some string' 是一条指令，由于找不到该指令，这里再次报错。
+# （这个例子中 'Variable=' 这部分会被当作仅对 'Some string' 起作用的赋值。）
 
 # 使用变量：
-echo $VARIABLE
+echo $Variable
-echo "$VARIABLE"
+echo "$Variable"
-echo '$VARIABLE'
+echo '$Variable'
 # 当你赋值 (assign) 、导出 (export)，或者以其他方式使用变量时，变量名前不加 $。
 # 如果要使用变量的值， 则要加 $。
 # 注意： ' (单引号) 不会展开变量（即会屏蔽掉变量）。
 
 
 # 在变量内部进行字符串代换
-echo ${VARIABLE/Some/A}
+echo ${Variable/Some/A}
-# 会把 VARIABLE 中首次出现的 "some" 替换成 “A”。
+# 会把 Variable 中首次出现的 "some" 替换成 “A”。
+
+# 变量的截取
+Length=7
+echo ${Variable:0:Length}
+# 这样会仅返回变量值的前7个字符
+
+# 变量的默认值
+echo ${Foo:-"DefaultValueIfFooIsMissingOrEmpty"}
+# 对 null (Foo=) 和空串 (Foo="") 起作用； 零（Foo=0）时返回0
+# 注意这仅返回默认值而不是改变变量的值
 
 # 内置变量：
 # 下面的内置变量很有用
@@ -55,26 +76,37 @@ echo "Last program return value: $?"
 echo "Script's PID: $$"
 echo "Number of arguments: $#"
 echo "Scripts arguments: $@"
-echo "Scripts arguments separeted in different variables: $1 $2..."
+echo "Scripts arguments separated in different variables: $1 $2..."
 
 # 读取输入：
 echo "What's your name?"
-read NAME # 这里不需要声明新变量
+read Name # 这里不需要声明新变量
-echo Hello, $NAME!
+echo Hello, $Name!
 
 # 通常的 if 结构看起来像这样：
 # 'man test' 可查看更多的信息
-if [ $NAME -ne $USER ]
+if [ $Name -ne $USER ]
 then
-    echo "Your name is you username"
+    echo "Your name isn't your username"
 else
-    echo "Your name isn't you username"
+    echo "Your name is your username"
 fi
 
 # 根据上一个指令执行结果决定是否执行下一个指令
-echo "Always executed" || echo "Only executed if first command fail"
+echo "Always executed" || echo "Only executed if first command fails"
 echo "Always executed" && echo "Only executed if first command does NOT fail"
 
+# 在 if 语句中使用 && 和 || 需要多对方括号
+if [ $Name == "Steve" ] && [ $Age -eq 15 ]
+then
+    echo "This will run if $Name is Steve AND $Age is 15."
+fi
+
+if [ $Name == "Daniya" ] || [ $Name == "Zach" ]
+then
+    echo "This will run if $Name is Daniya OR Zach."
+fi
+
 # 表达式的格式如下:
 echo $(( 10 + 5 ))
 
@@ -88,18 +120,54 @@ ls -l # 列出文件和目录的详细信息
 # 用下面的指令列出当前目录下所有的 txt 文件：
 ls -l | grep "\.txt"
 
+# 重定向输入和输出（标准输入，标准输出，标准错误）。
+# 以 ^EOF$ 作为结束标记从标准输入读取数据并覆盖 hello.py :
+cat > hello.py << EOF
+#!/usr/bin/env python
+from __future__ import print_function
+import sys
+print("#stdout", file=sys.stdout)
+print("#stderr", file=sys.stderr)
+for line in sys.stdin:
+    print(line, file=sys.stdout)
+EOF
+
 # 重定向可以到输出，输入和错误输出。
-python2 hello.py < "input.in"
+python hello.py < "input.in"
-python2 hello.py > "output.out"
+python hello.py > "output.out"
-python2 hello.py 2> "error.err"
+python hello.py 2> "error.err"
+python hello.py > "output-and-error.log" 2>&1
+python hello.py > /dev/null 2>&1
 # > 会覆盖已存在的文件， >> 会以累加的方式输出文件中。
+python hello.py >> "output.out" 2>> "error.err"
+
+# 覆盖 output.out , 追加 error.err 并统计行数
+info bash 'Basic Shell Features' 'Redirections' > output.out 2>> error.err
+wc -l output.out error.err
+
+# 运行指令并打印文件描述符 （比如 /dev/fd/123）
+# 具体可查看： man fd
+echo <(echo "#helloworld")
+
+# 以 "#helloworld" 覆盖 output.out:
+cat > output.out <(echo "#helloworld")
+echo "#helloworld" > output.out
+echo "#helloworld" | cat > output.out
+echo "#helloworld" | tee output.out >/dev/null
+
+# 清理临时文件并显示详情（增加 '-i' 选项启用交互模式）
+rm -v output.out error.err output-and-error.log
 
 # 一个指令可用 $( ) 嵌套在另一个指令内部：
 # 以下的指令会打印当前目录下的目录和文件总数
 echo "There are $(ls | wc -l) items here."
 
+# 反引号 `` 起相同作用，但不允许嵌套
+# 优先使用 $(  ).
+echo "There are `ls | wc -l` items here."
+
 # Bash 的 case 语句与 Java 和 C++ 中的 switch 语句类似:
-case "$VARIABLE" in
+case "$Variable" in
     # 列出需要匹配的字符串
     0) echo "There is a zero.";;
     1) echo "There is a one.";;
@@ -107,11 +175,37 @@ case "$VARIABLE" in
 esac
 
 # 循环遍历给定的参数序列:
-# 变量$VARIABLE 的值会被打印 3 次。
+# 变量$Variable 的值会被打印 3 次。
-# 注意 ` ` 和 $( ) 等价。seq 返回长度为 3 的数组。
+for Variable in {1..3}
-for VARIABLE in `seq 3`
 do
-    echo "$VARIABLE"
+    echo "$Variable"
+done
+
+# 或传统的 “for循环” ：
+for ((a=1; a <= 3; a++))
+do
+    echo $a
+done
+
+# 也可以用于文件
+# 用 cat 输出 file1 和 file2 内容
+for Variable in file1 file2
+do
+    cat "$Variable"
+done
+
+# 或作用于其他命令的输出
+# 对 ls 输出的文件执行 cat 指令。
+for Output in $(ls)
+do
+    cat "$Output"
+done
+
+# while 循环：
+while [ true ]
+do
+    echo "loop body here..."
+    break
 done
 
 # 你也可以使用函数
@@ -132,17 +226,52 @@ bar ()
 }
 
 # 调用函数
-foo "My name is" $NAME
+foo "My name is" $Name
 
 # 有很多有用的指令需要学习:
-tail -n 10 file.txt
 # 打印 file.txt 的最后 10 行
-head -n 10 file.txt
+tail -n 10 file.txt
 # 打印 file.txt 的前 10 行
-sort file.txt
+head -n 10 file.txt
 # 将 file.txt 按行排序
-uniq -d file.txt
+sort file.txt
 # 报告或忽略重复的行，用选项 -d 打印重复的行
-cut -d ',' -f 1 file.txt
+uniq -d file.txt
 # 打印每行中 ',' 之前内容
+cut -d ',' -f 1 file.txt
+# 将 file.txt 文件所有 'okay' 替换为 'great', （兼容正则表达式）
+sed -i 's/okay/great/g' file.txt
+# 将 file.txt 中匹配正则的行打印到标准输出
+# 这里打印以 "foo" 开头, "bar" 结尾的行
+grep "^foo.*bar$" file.txt
+# 使用选项 "-c" 统计行数
+grep -c "^foo.*bar$" file.txt
+# 如果只是要按字面形式搜索字符串而不是按正则表达式，使用 fgrep (或 grep -F)
+fgrep "^foo.*bar$" file.txt 
+
+
+# 以 bash 内建的 'help' 指令阅读 Bash 自带文档：
+help
+help help
+help for
+help return
+help source
+help .
+
+# 用 mam 指令阅读相关的 Bash 手册
+apropos bash
+man 1 bash
+man bash
+
+# 用 info 指令查阅命令的 info 文档 （info 中按 ? 显示帮助信息）
+apropos info | grep '^info.*('
+man info
+info info
+info 5 info
+
+# 阅读 Bash 的 info 文档：
+info bash
+info bash 'Bash Features'
+info bash 6
+info --apropos bash
 ```

zh-cn/groovy-cn.html.markdown

@@ -0,0 +1,420 @@
+---
+language: Groovy
+filename: learngroovy-cn.groovy
+contributors:
+    - ["Roberto Pérez Alcolea", "http://github.com/rpalcolea"]
+translators:
+    - ["Todd Gao", "http://github.com/7c00"]
+lang: zh-cn
+---
+
+Groovy - Java平台的动态语言。[了解更多。](http://www.groovy-lang.org/)
+
+```groovy
+
+/*
+  安装：
+
+  1) 安装 GVM - http://gvmtool.net/
+  2) 安装 Groovy： gvm install groovy
+  3) 启动 groovy 控制台，键入： groovyConsole
+
+*/
+
+//  双斜线开始的是单行注释
+/*
+像这样的是多行注释
+*/
+
+// Hello World
+println "Hello world!"
+
+/*
+  变量：
+
+  可以给变量赋值，以便稍后使用
+*/
+
+def x = 1
+println x
+
+x = new java.util.Date()
+println x
+
+x = -3.1499392
+println x
+
+x = false
+println x
+
+x = "Groovy!"
+println x
+
+/*
+  集合和映射
+*/
+
+//创建一个空的列表
+def technologies = []
+
+/*** 往列表中增加一个元素 ***/
+
+// 和Java一样
+technologies.add("Grails")
+
+// 左移添加，返回该列表
+technologies << "Groovy"
+
+// 增加多个元素
+technologies.addAll(["Gradle","Griffon"])
+
+/*** 从列表中删除元素 ***/
+
+// 和Java一样
+technologies.remove("Griffon")
+
+// 减号也行
+technologies = technologies - 'Grails'
+
+/*** 遍历列表 ***/
+
+// 遍历列表中的元素
+technologies.each { println "Technology: $it"}
+technologies.eachWithIndex { it, i -> println "$i: $it"}
+
+/*** 检查列表内容 ***/
+
+//判断列表是否包含某元素，返回boolean
+contained = technologies.contains( 'Groovy' )
+
+// 或
+contained = 'Groovy' in technologies
+
+// 检查多个元素
+technologies.containsAll(['Groovy','Grails'])
+
+/*** 列表排序 ***/
+
+// 排序列表（修改原列表）
+technologies.sort()
+
+// 要想不修改原列表，可以这样：
+sortedTechnologies = technologies.sort( false )
+
+/*** 列表操作 ***/
+
+//替换列表元素
+Collections.replaceAll(technologies, 'Gradle', 'gradle')
+
+//打乱列表
+Collections.shuffle(technologies, new Random())
+
+//清空列表
+technologies.clear()
+
+//创建空的映射
+def devMap = [:]
+
+//增加值
+devMap = ['name':'Roberto', 'framework':'Grails', 'language':'Groovy']
+devMap.put('lastName','Perez')
+
+//遍历映射元素
+devMap.each { println "$it.key: $it.value" }
+devMap.eachWithIndex { it, i -> println "$i: $it"}
+
+//判断映射是否包含某键
+assert devMap.containsKey('name')
+
+//判断映射是否包含某值
+assert devMap.containsValue('Roberto')
+
+//取得映射所有的键
+println devMap.keySet()
+
+//取得映射所有的值
+println devMap.values()
+
+/*
+  Groovy Beans
+
+  GroovyBeans 是 JavaBeans，但使用了更简单的语法
+
+  Groovy 被编译为字节码时，遵循下列规则。
+
+    * 如果一个名字声明时带有访问修饰符（public, private, 或者 protected），
+      则会生成一个字段（field）。
+
+    * 名字声明时没有访问修饰符，则会生成一个带有public getter和setter的
+      private字段，即属性（property）。
+
+    * 如果一个属性声明为final，则会创建一个final的private字段，但不会生成setter。
+
+    * 可以声明一个属性的同时定义自己的getter和setter。
+
+    * 可以声明具有相同名字的属性和字段，该属性会使用该字段。
+
+    * 如果要定义private或protected属性，必须提供声明为private或protected的getter
+      和setter。
+
+    * 如果使用显式或隐式的 this（例如 this.foo, 或者 foo）访问类的在编译时定义的属性，
+      Groovy会直接访问对应字段，而不是使用getter或者setter
+
+    * 如果使用显式或隐式的 foo 访问一个不存在的属性，Groovy会通过元类（meta class）
+      访问它，这可能导致运行时错误。
+
+*/
+
+class Foo {
+    // 只读属性
+    final String name = "Roberto"
+
+    // 只读属性，有public getter和protected setter
+    String language
+    protected void setLanguage(String language) { this.language = language }
+
+    // 动态类型属性
+    def lastName
+}
+
+/*
+  逻辑分支和循环
+*/
+
+//Groovy支持常见的if - else语法
+def x = 3
+
+if(x==1) {
+    println "One"
+} else if(x==2) {
+    println "Two"
+} else {
+    println "X greater than Two"
+}
+
+//Groovy也支持三元运算符
+def y = 10
+def x = (y > 1) ? "worked" : "failed"
+assert x == "worked"
+
+//for循环
+//使用区间（range）遍历
+def x = 0
+for (i in 0 .. 30) {
+    x += i
+}
+
+//遍历列表
+x = 0
+for( i in [5,3,2,1] ) {
+    x += i
+}
+
+//遍历数组
+array = (0..20).toArray()
+x = 0
+for (i in array) {
+    x += i
+}
+
+//遍历映射
+def map = ['name':'Roberto', 'framework':'Grails', 'language':'Groovy']
+x = 0
+for ( e in map ) {
+    x += e.value
+}
+
+/*
+  运算符
+
+  在Groovy中以下常用运算符支持重载：
+  http://www.groovy-lang.org/operators.html#Operator-Overloading
+
+  实用的groovy运算符
+*/
+//展开（spread）运算符：对聚合对象的所有元素施加操作
+def technologies = ['Groovy','Grails','Gradle']
+technologies*.toUpperCase() // 相当于 technologies.collect { it?.toUpperCase() }
+
+//安全导航（safe navigation）运算符：用来避免NullPointerException
+def user = User.get(1)
+def username = user?.username
+
+
+/*
+  闭包
+  Groovy闭包好比代码块或者方法指针，它是一段代码定义，可以以后执行。
+
+  更多信息见：http://www.groovy-lang.org/closures.html
+*/
+//例子：
+def clos = { println "Hello World!" }
+
+println "Executing the Closure:"
+clos()
+
+//传参数给闭包
+def sum = { a, b -> println a+b }
+sum(2,4)
+
+//闭包可以引用参数列表以外的变量
+def x = 5
+def multiplyBy = { num -> num * x }
+println multiplyBy(10)
+
+// 只有一个参数的闭包可以省略参数的定义
+def clos = { print it }
+clos( "hi" )
+
+/*
+  Groovy可以记忆闭包结果 [1][2][3]
+*/
+def cl = {a, b ->
+    sleep(3000) // 模拟费时操作
+    a + b
+}
+
+mem = cl.memoize()
+
+def callClosure(a, b) {
+    def start = System.currentTimeMillis()
+    mem(a, b)
+    println "Inputs(a = $a, b = $b) - took ${System.currentTimeMillis() - start} msecs."
+}
+
+callClosure(1, 2)
+callClosure(1, 2)
+callClosure(2, 3)
+callClosure(2, 3)
+callClosure(3, 4)
+callClosure(3, 4)
+callClosure(1, 2)
+callClosure(2, 3)
+callClosure(3, 4)
+
+/*
+  Expando
+
+  Expando类是一种动态bean类，可以给它的实例添加属性和添加闭包作为方法
+
+  http://mrhaki.blogspot.mx/2009/10/groovy-goodness-expando-as-dynamic-bean.html
+*/
+  def user = new Expando(name:"Roberto")
+  assert 'Roberto' == user.name
+
+  user.lastName = 'Pérez'
+  assert 'Pérez' == user.lastName
+
+  user.showInfo = { out ->
+      out << "Name: $name"
+      out << ", Last name: $lastName"
+  }
+
+  def sw = new StringWriter()
+  println user.showInfo(sw)
+
+
+/*
+  元编程(MOP)
+*/
+
+//使用ExpandoMetaClass增加行为
+String.metaClass.testAdd = {
+    println "we added this"
+}
+
+String x = "test"
+x?.testAdd()
+
+//拦截方法调用
+class Test implements GroovyInterceptable {
+    def sum(Integer x, Integer y) { x + y }
+
+    def invokeMethod(String name, args) {
+        System.out.println "Invoke method $name with args: $args"
+    }
+}
+
+def test = new Test()
+test?.sum(2,3)
+test?.multiply(2,3)
+
+//Groovy支持propertyMissing，来处理属性解析尝试
+class Foo {
+   def propertyMissing(String name) { name }
+}
+def f = new Foo()
+
+assertEquals "boo", f.boo
+
+/*
+  类型检查和静态编译
+  Groovy天生是并将永远是一门动态语言，但也支持类型检查和静态编译
+
+  更多： http://www.infoq.com/articles/new-groovy-20
+*/
+//类型检查
+import groovy.transform.TypeChecked
+
+void testMethod() {}
+
+@TypeChecked
+void test() {
+    testMeethod()
+
+    def name = "Roberto"
+
+    println naameee
+
+}
+
+//另一例子
+import groovy.transform.TypeChecked
+
+@TypeChecked
+Integer test() {
+    Integer num = "1"
+
+    Integer[] numbers = [1,2,3,4]
+
+    Date date = numbers[1]
+
+    return "Test"
+
+}
+
+//静态编译例子
+import groovy.transform.CompileStatic
+
+@CompileStatic
+int sum(int x, int y) {
+    x + y
+}
+
+assert sum(2,5) == 7
+
+
+```
+
+## 进阶资源
+
+[Groovy文档](http://www.groovy-lang.org/documentation.html)
+
+[Groovy web console](http://groovyconsole.appspot.com/)
+
+加入[Groovy用户组](http://www.groovy-lang.org/usergroups.html)
+
+## 图书
+
+* [Groovy Goodness] (https://leanpub.com/groovy-goodness-notebook)
+
+* [Groovy in Action] (http://manning.com/koenig2/)
+
+* [Programming Groovy 2: Dynamic Productivity for the Java Developer] (http://shop.oreilly.com/product/9781937785307.do)
+
+[1] http://roshandawrani.wordpress.com/2010/10/18/groovy-new-feature-closures-can-now-memorize-their-results/
+[2] http://www.solutionsiq.com/resources/agileiq-blog/bid/72880/Programming-with-Groovy-Trampoline-and-Memoize
+[3] http://mrhaki.blogspot.mx/2011/05/groovy-goodness-cache-closure-results.html
+
+
+

zh-cn/javascript-cn.html.markdown

@@ -341,7 +341,7 @@ var myFunc = myObj.myFunc;
 myFunc(); // = undefined
 
 // 相应的，一个函数也可以被指定为一个对象的方法，并且可以通过`this`访问
-// 这个对象的成员，即使在行数被定义时并没有依附在对象上。
+// 这个对象的成员，即使在函数被定义时并没有依附在对象上。
 var myOtherFunc = function(){
     return this.myString.toUpperCase();
 }