Generated models and the ω-rule: The nondeterministic case

Abstract

Abstract.A language for specifying nondeterminisuc operations which generalizes the equational specificauon language is introduced. Then, vanous notions of generated multimodels are discussed and sufficmnt condiuons for the existence of quasi-initial semanucs of nondeterministic specifications are given. Two calculi are introduced: NEQ and NIP. The former is sound and complete with respect to the class of all muhimodels. The latter is an extension of the former veuh the ta-mle. It is sound and complete with respect to one of the classes of the generated mulnmodels. The calcuh reduce to the respective determimstic calculi whenever the specffl cation involves only deterministic operations.