Search-Based Ambiguity Detection in Context-Free Grammars

Context Free Grammars (CFGs) can be ambiguous, allowing inputs to be parsed in more than one way, something that is undesirable for uses such as programming languages. However, statically detecting ambiguity is undecidable. Though approximation techniques have had some success in uncovering ambiguity, they can struggle when the ambiguous subset of the grammar is large. In this paper, we describe a simple search-based technique which appears to have a better success rate in such cases