A mathematical function that evaluates an arithmetic expression and returns a value (either a number or text string) based on zero, one, or any number of arguments. You can use an evaluated function in any arithmetic expression in an AHDL; you cannot use an evaluated function in a Boolean expression.

The Define Statement is used to create evaluated functions. The following example shows a Define Statement that defines the evaluated function EX:

DEFINE EX(a,b) = (a > b) ? a : b;