First Class Call Stacks: Exploring Head Reduction

Philip Johnson-Freyd, Paul Downen, Zena M. Ariola
2016 Electronic Proceedings in Theoretical Computer Science  
Weak-head normalization is inconsistent with functional extensionality in the call-by-name λ-calculus. We explore this problem from a new angle via the conflict between extensionality and effects. Leveraging ideas from work on the λ-calculus with control, we derive and justify alternative operational semantics and a sequence of abstract machines for performing head reduction. Head reduction avoids the problems with weak-head reduction and extensionality, while our operational semantics and
more » ... iated abstract machines show us how to retain weak-head reduction's ease of implementation.
doi:10.4204/eptcs.212.2 fatcat:ho6eyjw52bachihul6few2szcm