Monadic, Prompt Lazy Assertions in Haskell

Abstract. Assertions test expected properties of run-time values without disrupting the normal computation of a program. We present a library for enriching Haskell programs with assertions. Expected properties can be specified in a parser-combinator like language. The assertions are lazy: they do not force evaluation but only examine what is evaluated by the program. They are also prompt: assertion failure is reported as early as possible. The implementation is based on lazy observations and continuation-based coroutines.

• Type: Conference
• Year: 2007
• Where: APLAS
• Authors: Olaf Chitil, Frank Huch
• Keywords: APLAS 2007, Normal Computation, Programming Languages, Run-time Values, Test Expected Properties