翻訳と辞書 Words near each other ・ Two-hander ・ Two-Headed Monster ・ Two-Headed Poems ・ Two-Higgs-doublet model ・ Two-hybrid screening ・ Two-in, two-out ・ Two-Lane Blacktop ・ Two-Lane Blacktop (song) ・ Two-lane expressway ・ Two-leaved Solomon's seal ・ Two-legged tie ・ Two-letter country codes ・ Two-letter English words ・ Two-level defense ・ Two-level game theory ・ Two-level grammar ・ Two-level scheduling ・ Two-level utilitarianism ・ Two-line element set ・ Two-lined climbing salamander ・ Two-lined monocle bream ・ Two-liter bottle ・ Two-man rule ・ Two-man saw ・ Two-mass-skate bicycle ・ Two-Micron Sky Survey ・ Two-Mile Borris ・ Two-Minute Drill ・ Two-minute drill ・ Two-minute silence Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Two-level grammar ： ウィキペディア英語版 Two-level grammar A two-level grammar is a formal grammar that is used to generate another formal grammar (), such as one with an infinite rule set (). This is how a Van Wijngaarden grammar was used to specify Algol68 (). A context free grammar that defines the rules for a second grammar can yield an effectively infinite set of rules for the derived grammar. This makes such two-level grammars more powerful than a single layer of context free grammar, because generative two-level grammars have actually been shown to be Turing complete.〔Sintzoff, M. "Existence of van Wijngaarden syntax for every recursively enumerable set", Annales de la Société Scientifique de Bruxelles 2 (1967), 115-118.〕 ''Two-level grammar'' can also refer to a formal grammar for a two-level formal language, which is a formal language specified at two levels, for example, the levels of words and sentences. ==Example== A well-known non-context-free language is :$\backslash .$ A two-level grammar for this language is the metagrammar :N ::= 1 | N1 :X ::= a | b together with grammar schema :Start ::= $\backslash langle\; a^N\; \backslash rangle\backslash langle\; b^N\; \backslash rangle\backslash langle\; a^N\; \backslash rangle$ :$\backslash langle\; X^\; \backslash rangle$ ::= $\backslash langle\; X^N\; \backslash rangle\; X$ :$\backslash langle\; X^1\; \backslash rangle$ ::= X 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Two-level grammar」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.