Summary: Automated Termination Analysis for Haskell:
From Term Rewriting to Programming Languages #
J˜urgen Giesl, Stephan Swiderski, Peter Schneider--Kamp, and Ren’e Thiemann
LuFG Informatik 2, RWTH Aachen, Ahornstr. 55, 52074 Aachen, Germany,
{giesl,swiderski,psk,thiemann}@informatik.rwth­aachen.de
Abstract. There are many powerful techniques for automated termi­
nation analysis of term rewriting. However, up to now they have hardly
been used for real programming languages. We present a new approach
which permits the application of existing techniques from term rewriting
in order to prove termination of programs in the functional language Has­
kell. In particular, we show how termination techniques for ordinary re­
writing can be used to handle those features of Haskell which are missing
in term rewriting (e.g., lazy evaluation, polymorphic types, and higher­
order functions). We implemented our results in the termination prover
AProVE and successfully evaluated them on existing Haskell­libraries.
1 Introduction
We show that termination techniques for term rewrite systems (TRSs) are also
useful for termination analysis of programming languages like Haskell. Of course,
any program can be translated into a TRS, but in general, it is not obvious how
to obtain TRSs suitable for existing automated termination techniques. Adapting

Source: Ábrahám, Erika - Fachgruppe Informatik, Rheinisch Westfälische Technische Hochschule Aachen (RWTH)

Collections: Computer Technologies and Information Sciences