We introduce the concept of logical full abstraction, generalising the usual equational notion. We consider the language PCF and two extensions with ``parallel'' operations. The main result is that, for standard interpretations, logical full abstraction is equivalent to equational full abstraction together with universality; the proof involves constructing enumeration operators. We also consider restrictions on logical complexity and on the level of types.ECS-LFCS-97-353.
This report is available in the following formats: