Monadic compiler calculation (functional pearl)

Bahr and Hutton recently developed a new approach to calculating correct compilers directly from specifications of their correctness. However, the methodology only considers converging behaviour source language, which means that compiler could potentially produce arbitrary, erroneous code for programs diverge. In this article, we show how can naturally be extended support calculation address both convergent divergent simultaneously , without need separate reasoning each aspect. Our is based on use partiality monad make divergence explicit, together with strong bisimilarity equational-style calculations, but also generalises other forms effect by changing underlying monad.