Function prototype: Difference between revisions

=={{header|Go}}==

While the language specification does not use the word prototype it states, "A function declaration may omit the body. Such a declaration provides the signature for a function implemented outside Go, such as an assembly routine." This is the closest analogy to a C (e.g.) prototype.

Function declarations whether with a body or without must be "top level" declarations, that is, after the package clause and outside of any other function. Examples of function delarations without bodies are,

<lang go>func a() // function with no arguments

func b(x, y int) // function with two arguments

func c(...int) // varargs are called "variadic parameters" in Go.</lang>

Go does not directly support optional or named parameters and does not have any concept of procedures or subroutines as distinct from functions.

Otherwise, Go does have the concept of a function signature which includes parameters and return values. Go is strongly typed and functions are first class objects so function signatures are used in a variety of ways. These might be considered distinct from the concept of function prototype.