Generalized context-free grammar

Generalized context-free grammar (GCFG) is a grammar formalism that expands on context-free grammars by adding potentially non-context-free composition functions to rewrite rules.^[1] Head grammar (and its weak equivalents) is an instance of such a GCFG which is known to be especially adept at handling a wide variety of non-CF properties of natural language.

^ Weir, David Jeremy (Sep 1988). Characterizing mildly context-sensitive grammar formalisms (PDF) (Ph.D.). Paper. Vol. AAI8908403. University of Pennsylvania Ann Arbor.

[weir1988-1] Weir, David Jeremy (Sep 1988). Characterizing mildly context-sensitive grammar formalisms (PDF) (Ph.D.). Paper. Vol. AAI8908403. University of Pennsylvania Ann Arbor.

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