Finding Grammars That Are More Than Context-Free, But Not Fully Context-Sensitive
نویسنده
چکیده
This survey paper describes several extensions of context-free grammars as defined in the Chomsky hierarchy. These augmentations use a variety of different strategies to create grammars that generate all context-free and some context-sensitive languages. The basic concepts of each of these extensions will be examined, as well as whether the enhanced grammars inherited some of the desirable properties normally associated with contextfree grammars. In addition, a brief examination of non-Chomsky-related augmentations is included to show that the definition of “extension” is open to interpretation.
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تاریخ انتشار 2006