Functions

A function with two parameters a:A and b:B, and return type C, is declared as:

function f(a:A, b:B) -> C {
  c:C;
  // do something
  return c;
}

For a function without a return value, omit the ->:

function f(a:A, b:B) {
  // do something
}

For a function without parameters, use empty parentheses:

function f() {
  // do something
}

Functions are called by giving arguments in parentheses:

f(a, b)

When calling a function without parameters, use empty parentheses:

f()

Generic functions

A function declaration may include type parameters that are provided arguments when the function is called. These are declared using angle brackets in the function declaration:

function f<T,U>(a:T, b:U) {
  // do something
}

Such a function is a generic function. When a generic function is called, type arguments can be provided:

f<Real,Integer>(1.0, 2);

Here, T becomes Real and U becomes Integer. In many cases it is unnecessary to explicitly provide these type arguments, however, as the compiler can deduce them itself. In this particular example, using f(1.0, 2) is sufficient. Sometimes the compiler cannot deduce them itself, and they must be specified explicitly.