Function Prototypes

• Functions may appear in any order in a program ---> difficulties for the compiler in checking any calls which appear before the function is defined.
  
  
• Legal, but may require compiler to make assumptions.
  
  
• Use prototypes!

/* Prototype for triple : */ double triple(double); ... ... /* Call triple : */ y = triple(3.3 * z1); ... ... /* Declare triple : */ double triple(double x) { return x*3; }