Editing Generalized phrase structure grammar (section)

== Goals ==
One of the chief goals of GPSG is to show that the syntax of natural languages can be described by CFGs (written as [[ID/LP grammar]]s), with some suitable conventions intended to make writing such grammars easier for syntacticians. Among these conventions are a sophisticated [[feature structure]] system and so-called "meta-rules", which are rules generating the productions of a context-free grammar. GPSG further augments syntactic descriptions with semantic annotations that can be used to compute the compositional meaning of a sentence from its syntactic derivation tree.<ref>{{cite journal |last1=Ristad |first1=Eric |title=REVISED GENERALIZED PHRASE STRUCTURE GRAMMAR |url=http://aclweb.org/anthology/P87-1034 |website=aclweb.org |year=1987 |pages=243–250 |publisher=The Association for Computational Linguistics |doi=10.3115/981175.981209 |accessdate=16 December 2018|doi-access=free }}</ref> However, it has been argued (for example by [[Robert Berwick]]) that these extensions require [[parser|parsing]] algorithms of a higher order of [[Analysis of algorithms|computational complexity]] than those used for basic CFGs.