Sloth – A Tool for Checking Minimal-Strictness

Abstract

We present a light-weight tool called Sloth which assists programmers in identifying unnecessarily strict first order functions. Sloth reports counterexamples in form of a partial value, the corresponding result of the tested function and a recommended result. We present examples where the hints reported by Sloth can be used to improve a function with respect to memory behaviour, non-termination, and performance in the context of functional-logic programming. Furthermore we give an example-driven introduction into the basics of the implementation of Sloth. To improve the results in comparison to an existing approach we use additional constraints to assure that Sloth’s suggestions are implementable without employing parallelism.