A Use Case Grammar for Requirements Specification

This paper proposes a use case grammar for the specification of functional requirements. The proposed grammar is defined in EBNF, tested in ANTLR and provides syntactic and semantic rules for writing use case specifications in semi-formal natural language. Such formalization not only helps to make the expression of requirements more disciplined, understandable, well-structured and validated, but it also makes easier their conversion into diagrammatic notations, such as use case and sequence diagrams. It also helps in reducing the time to identify and specify requirements, in diminishing redundancies, inconsistencies and omissions, and, generally, in producing better requirements.