Abstract

Towards a Theory of Tracing for Functional Programs

The tracer Hat records in a detailed trace the computation of a program written in the lazy functional language Haskell. The trace can then be viewed in various ways to support program comprehension and debugging. Here we describe a model of the trace that captures its essential properties and allows formal reasoning. The trace structure was inspired by standard graph rewriting implementations of functional languages. The trace is a graph which is constructed by graph rewriting but goes beyond simple term graphs.