Opal (programming language)
From Seo Wiki - Search Engine Optimization and Programming Languages
This is an example OPAL program, which calculates the GCD recursively.
SIGNATURE GCD FUN GCD: nat ** nat -> nat
IMPLEMENTATION GCD IMPORT Nat COMPLETELY DEF GCD(a,b) == IF a % b = 0 THEN b ELSE IF a-b < b THEN GCD(b,a-b) ELSE GCD(a-b,b) FI FI
|File:HelloWorld.svg||This programming language-related article is a stub. You can help Wikipedia by expanding it.|