Opal (programming language)

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OPAL (OPtimized Applicative Language) is a functional programming language first developed at the Technical University of Berlin.

Contents

There is a later framework for static code analysis also called Opal. [1]

Example program

This is an example OPAL program, which calculates the GCD recursively.

Signature file (declaration)
SIGNATURE GCD    FUN GCD: nat ** nat -> nat
Implementation file (definition)
IMPLEMENTATION GCD    IMPORT Nat COMPLETELYDEF GCD(a,b) == IF a % b = 0 THEN b                        ELSE IF a-b < b THEN GCD(b,a-b)                            ELSE GCD(a-b,b)                        FIFI

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References

  1. "Home page". OPAL Project. Retrieved 2023-11-25.