Functions Describes user defined functions. Understanding functions This is an introduction to functions. FUNCTION definitions A FUNCTION definition defines a named procedure with a set of statements. Function parameters Functions can take parameters, to specialize their behavior. Scope of a function A functions can be isolated to control its visibility to other modules. Local symbol definition Symbols defined inside a function body are only visible to the function. Calling functions Functions can be invoked, to execute the code they define. Returning values A function can return values with the RETURN instruction. Function references Function can be referenced and invoked dynamically in a CALL instruction, or in an expression. FUNCTION func-spec The FUNCTION keyword provides the reference to the specified function. Examples Function definition examples.