Abstract
Tracing and Debugging Haskell Programs with Hat
The lack of tools for tracing and debugging has deterred software
developers from using Haskell. The tracing method of conventional
debuggers is unsuitable for a lazy functional language such as Haskell.
I will present Hat, a Haskell tracer which is currently developed within
an EPSRC project at the University of York. The trace shows the
relationships between values and redexes evaluated during a program run.
The trace is explored by walking backwards from a value to the redexes
that lead to the creation of the value. I will discuss the design, usage
and implementation of the system and finally mention some problems of
the current system.
If time permits, I will also shortly present two other systems for
tracing Haskell, namely Freja and Hood.