Address @levibostian's concerns for #800

This commit is contained in:
Matt Kline 2014-10-17 18:42:30 -07:00
parent fbf3c6d588
commit 03d1bc5ed9

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@ -7,12 +7,14 @@ contributors:
lang: en
---
C++ was designed as a systems programming language that
C++ is a systems programming language that,
[according to its inventor Bjarne Stroustrup](http://channel9.msdn.com/Events/Lang-NEXT/Lang-NEXT-2014/Keynote),
was designed to
- is a "better C"
- supports data abstraction
- supports object-oriented programming
- supports generic programming
- be a "better C"
- support data abstraction
- support object-oriented programming
- support generic programming
Though its syntax can be more difficult or complex than newer languages,
it is widely used because it compiles to native instructions that can be
@ -32,9 +34,21 @@ one of the most widely-used programming languages.
// A main() function in C++ should return an int,
// though void main() is accepted by most compilers (gcc, clang, etc.)
int main() // or int main(int argc, char** argv)
// 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)
{
return 0; // Can also end without return statement
// Command line arguments are passed in by argc and argv in the same way
// they are in C.
// argc indicates the number of arguments,
// and argv is an array of C-style strings (char*)
// representing the arguments.
// The first argument is the name by which the program was called.
// argc and argv can be omitted if you do not care about arguments,
// giving the function signature of int main()
// An exit status of 0 indicates success.
return 0;
}
// In C++, character literals are one byte.
@ -82,21 +96,33 @@ void print(int myInt)
int main()
{
printing("Hello"); // Resolves to void print(const char*)
printing(15); // Resolves to void print(int)
print("Hello"); // Resolves to void print(const char*)
print(15); // Resolves to void print(int)
}
/////////////////////////////
// Default function arguments
/////////////////////////////
void two_ints(int a = 1, int b = 4);
// You can provide default arguments for a function
// if they are not provided by the caller.
void doSomethingWithInts(int a = 1, int b = 4)
{
// Do something with the ints here
}
int main()
{
two_ints(); // a = 1, b = 4
two_ints(20); // a = 20, b = 4
two_ints(20, 5); // a = 20, b = 5
doSomethingWithInts(); // a = 1, b = 4
doSomethingWithInts(20); // a = 20, b = 4
doSomethingWithInts(20, 5); // a = 20, b = 5
}
// Default arguments must be at the end of the arguments list.
void invalidDeclaration(int a = 1, int b) // Error!
{
}
@ -106,7 +132,7 @@ int main()
// Namespaces provide separate scopes for variable, function,
// and other declarations.
// Namespaces can be nested
// Namespaces can be nested.
namespace First {
namespace Nested {
@ -362,7 +388,7 @@ public:
Point() { };
// The following syntax is known as an initialization list
// and is the proper way to initialize class member values
// and is the proper way to initialize class member values
Point (double a, double b) :
x(a),
y(b)