Facilitating formal specification acquisition by using recursive functions on context-free languages

Although formal specification techniques are very useful in software development, the acquisition of formal specification is a difficult task. This paper presents the formal software specification language LFC, which is designed to facilitate the acquisition and validation of formal specifications. LFC relies on a new kind of recursive functions, i. e. recursive functions on context-free languages, for semantic aspect and uses context-free languages for syntactic aspect of specifications. Specification in LFC and the validation are entirely machine-aided. Specification is mainly facilitated through grammatical learning technique and machine-aided function construction. Validation is facilitated by sample recognition and generation techniques and rapid prototyping technique. A formal specification acquisition system SAQ has been implemented, several non-trivial examples have been developed using SAQ.