Updated scala for line lengths

scala.html.markdown

@@ -8,9 +8,7 @@ filename: learn.scala
 
 Scala - the scalable language
 
-```c
-
-
+```scala
 
 /*
   Set yourself up:
@@ -21,7 +19,8 @@ Scala - the scalable language
 
   scala>
 
-  This is the so called REPL. You can run commands in the REPL. Let's do just that:
+  This is the so called REPL. You can run commands in the REPL. Let's do just
+  that:
 */
 
 println(10) // prints the integer 10
@@ -37,7 +36,8 @@ println("Hello world!")
 print("Hello world")
 
 // Declaring values is done using either var or val
-// val declarations are immutable, whereas var's are mutable. Immutablility is a good thing.
+// val declarations are immutable, whereas var's are mutable. Immutablility is 
+// a good thing.
 val x = 10 // x is now 10
 x = 20 // error: reassignment to val
 var x = 10 
@@ -74,7 +74,8 @@ true == false // false
   scala> 1 + 7
   res29: Int = 8
 
-  This means the result of evaluating 1 + 7 is an object of type Int with a value of 8
+  This means the result of evaluating 1 + 7 is an object of type Int with a
+  value of 8
 
   1+7 will give you the same result
 */
@@ -94,14 +95,16 @@ val sq = (x:Int) => x * x
    
    sq: Int => Int = <function1>	
 
-   Which means that this time we gave an explicit name to the value - sq is a function that take an Int and returns Int.
+   Which means that this time we gave an explicit name to the value - sq is a
+   function that take an Int and returns Int.
 
    sq can be executed as follows:
 */
 
-sq(10)   // Gives you this: res33: Int = 100. The result is the Int with a value 100
+sq(10)   // Gives you this: res33: Int = 100.
 
-// Scala allows methods and functions to return, or take as parameters, other functions or methods.
+// Scala allows methods and functions to return, or take as parameters, other
+// functions or methods.
 
 val add10: Int => Int = _ + 10 // A function taking an Int and returning an Int
 List(1, 2, 3) map add10 // List(11, 12, 13) - add10 is applied to each element
@@ -109,10 +112,12 @@ List(1, 2, 3) map add10 // List(11, 12, 13) - add10 is applied to each element
 // Anonymous functions can be used instead of named functions:
 List(1, 2, 3) map (x => x + 10)
 
-// And the underscore symbol, can be used if there is just one argument to the anonymous function. It gets bound as the variable
+// And the underscore symbol, can be used if there is just one argument to the
+// anonymous function. It gets bound as the variable
 List(1, 2, 3) map (_ + 10)
 
-TODO // If the anonymous block AND the function you are applying both take one argument, you can even omit the underscore
+// If the anonymous block AND the function you are applying both take one
+// argument, you can even omit the underscore
 List("Dom", "Bob", "Natalia") foreach println
 
 
@@ -136,7 +141,8 @@ val s = Set(1, 3, 7)
 s(0)
 s(1)
 
-/* Look up the documentation of map here - http://www.scala-lang.org/api/current/index.html#scala.collection.immutable.Map 
+/* Look up the documentation of map here - 
+ * http://www.scala-lang.org/api/current/index.html#scala.collection.immutable.Map 
  * and make sure you can read it
  */
 
@@ -156,7 +162,8 @@ val divideInts = (x:Int, y:Int) => (x / y, x % y)
 
 divideInts(10,3) // The function divideInts gives you the result and the remainder
 
-// To access the elements of a tuple, use _._n where n is the 1-based index of the element
+// To access the elements of a tuple, use _._n where n is the 1-based index of
+// the element
 val d = divideInts(10,3)
 
 d._1
@@ -175,7 +182,8 @@ sSquared.filter(_ < 10)
 
 sSquared.reduce (_+_)
 
-// The filter function takes a predicate (a function from A -> Boolean) and selects all elements which satisfy the predicate
+// The filter function takes a predicate (a function from A -> Boolean) and
+// selects all elements which satisfy the predicate
 List(1, 2, 3) filter (_ > 2) // List(3)
 List(
   Person(name = "Dom", age = 23), 
@@ -183,7 +191,8 @@ List(
 ).filter(_.age > 25) // List(Person("Bob", 30))
 
 
-// Scala a foreach method defined on certain collections that takes a type returning Unit (a void method)
+// Scala a foreach method defined on certain collections that takes a type
+// returning Unit (a void method)
 aListOfNumbers foreach (x => println(x))
 aListOfNumbers foreach println
 
@@ -200,8 +209,8 @@ for { n <- nSquared2 if n < 10 } yield n
 
 for { n <- s; nSquared = n * n if nSquared < 10} yield nSquared
 
-/* NB Those were not for loops. The semantics of a for loop is 'repeat', whereas a for-comprehension
-   defines a relationship between two sets of data. Research this further  */
+/* NB Those were not for loops. The semantics of a for loop is 'repeat', whereas
+   a for-comprehension defines a relationship between two sets of data. */
 
 
 
@@ -212,8 +221,8 @@ val r = 1 to 5
 r.foreach( println )
 
 r foreach println     
-// NB: Scala is quite lenien when it comes to dots and brackets - study the rules separately. This 
-// helps write DSLs and APIs that read like English
+// NB: Scala is quite lenient when it comes to dots and brackets - study the
+// rules separately. This helps write DSLs and APIs that read like English
 
 (5 to 1 by -1) foreach ( println )
 
@@ -223,20 +232,25 @@ while (i < 10) {  println("i " + i); i+=1  }
 
 while (i < 10) {  println("i " + i); i+=1  }   // Yes, again. What happened? Why?
 
-i    // Show the value of i. Note that while is a loop in the classical sense - it executes
-     // sequentially while changing the loop variable. while is very fast, faster that Java
-     // loops, but using the combinators and comprehensions above is easier to understand
-     // and parallelize
+i    // Show the value of i. Note that while is a loop in the classical sense -
+     // it executes sequentially while changing the loop variable. while is very
+     // fast, faster that Java // loops, but using the combinators and
+     // comprehensions above is easier to understand and parallelize
 
 // A do while loop
-do { 
+do {
   println("x is still less then 10"); 
   x += 1
 } while (x < 10)
 
-// Tail recursion is an idiomatic way of doing recurring things in Scala. Recursive functions need an 
-// explicit return type, the compiler can't infer it. Here it's Unit.
-def showNumbersInRange(a:Int, b:Int):Unit = { print(a); if (a < b) showNumbersInRange(a+1, b)  }
+// Tail recursion is an idiomatic way of doing recurring things in Scala.
+// Recursive functions need an explicit return type, the compiler can't infer it.
+// Here it's Unit.
+def showNumbersInRange(a:Int, b:Int):Unit = {
+  print(a)
+  if (a < b)
+    showNumbersInRange(a + 1, b)
+}
 
 
 
@@ -268,7 +282,8 @@ class Dog {
   }
 }
 
-// Classes can contain nearly any other construct, including other classes, functions, methods, objects, case classes, traits etc.
+// Classes can contain nearly any other construct, including other classes,
+// functions, methods, objects, case classes, traits etc.
 
 
 
@@ -285,7 +300,8 @@ Person("George", "1234") == Person("Kate", "1236")
 
 val me = Person("George", "1234")
 
-me match { case Person(name, number) => "We matched someone : " + name + ", phone : " + number }
+me match { case Person(name, number) => {
+            "We matched someone : " + name + ", phone : " + number }}
 
 me match { case Person(name, number) => "Match : " + name; case _ => "Hm..." }
 
@@ -303,7 +319,7 @@ kate match { case Person("Kate", _) => "Girl"; case Person("George", _) => "Boy"
 
 // Regular expressions
 
-val email = "(.*)@(.*)".r          // The suffix .r invokes method r on String, which makes it a Regex
+val email = "(.*)@(.*)".r  // Invoking r on String makes it a Regex
 
 val email(user, domain) = "henry@zkpr.com"
 
@@ -319,7 +335,9 @@ val email(user, domain) = "henry@zkpr.com"
 'a' // A Scala Char
 'Single quote strings don't exist' // Error
 "Strings have the usual Java methods defined on them".length
-"They also have some extra Scala methods.".reverse // See scala.collection.immutable.StringOps
+"They also have some extra Scala methods.".reverse
+
+// Seealso:  scala.collection.immutable.StringOps
 
 println("ABCDEF".length)
 println("ABCDEF".substring(2, 6))
@@ -334,7 +352,8 @@ println(s"My second daughter is ${a(2-1)} years old")
 // Some characters need to be 'escaped', e.g. a double quote inside a string:
 val a = "They stood outside the \"Rose and Crown\""
 
-// Triple double-quotes allow for strings to span multiple rows and contain funny characters
+// Triple double-quotes let strings span multiple rows and contain quotes
+
 val html = """<form id="daform">
                 <p>Press belo', Joe</p>
              |  <input type="submit">
@@ -359,7 +378,8 @@ import scala.collection.immutable{ List => ImmutableList }
 // Import all classes, except some. The following excludes Map and Set:
 import scala.collection.immutable.{Map => _, Set => _, _}
 
-// Your programs entry point is defined in an scala file using an object, with a single method, main:
+// Your programs entry point is defined in an scala file using an object, with a
+// single method, main:
 object Application {
   def main(args: Array[String]): Unit = {
     // stuff goes here.