Functions

Defining and invoking functions

A function definition has the following form:

<RETURNTYPE> <FUNCTIONNAME> ( <ARGUMENTLIST?> ) { <FUNCTIONBODY> }

The returntype is either the special placeholder "void", a fundamentaltype or a user defined type. Functionname is a freely chosen identifier for the function. An Argumentlist is optional. Ommitting the argument list specifies that the function takes no arguments.

Examples of legal function definitions are:

float giveme_pi () { return 3.14f; } // returns pi (very inaccurately) int add_numbers (int a, int b, int c) // function that adds 3 numbers { // and returns the result return a + b + c; } void noarguments_voidreturn () // a void function with no arguments { dosomething(); }

Recursion

Recursive function invocation is supported by butter. That means the the classic recursive fibonacci program will work as usual.

/* recursive fibonacci function, only good for benchmarks */ int fibo (int a) { if (a <= 1) return 1; return fibo (a - 2) + fibo(a - 1); }