: Some of the shortcomings of using refinement alone as the means of passing from high level simple models to actual detailed implementations are reviewed. Retrenchment is presente...
Retrenchment is presented in a simple relational framework as a more flexible development concept than refinement for capturing the early preformal stages of development, and brie...
Abstract. Noting that the usual `propositionally' based way of composing retrenchments can yield many `junk' cases, alternative approaches to composition are introduced (...
Simple retrenchment is briefly reviewed in the B language of J.-R. Abrial [1] as a liberalisation of classical refinement, for the formal description of application developments ...