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        "description": "The LR(k) condition belongs to a grammar with specified lookahead k; two grammars for the same language may differ. Linear parsing claims concern input length for a fixed grammar/parser, and do not bound parser-construction cost or table size. Not all context-free grammars qualify. The whole deterministic-language and unspecified-lookahead undecidability proofs are outside this selected reading.",
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          "citation": "Donald E. Knuth, On the Translation of Languages from Left to Right, Information and Control 8(6) (1965), 607–639",
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      "statement": "# Knuth: LR grammars and left-to-right parser construction\n\nKnuth defined LR(k) grammars through uniquely determined reductions with fixed lookahead. He connected that condition with finite methods for testing a specified grammar and generating stack-based shift/reduce recognizers.\n\nA parser reads the input while deciding when a recognized part should be reduced by a grammar production. LR(k) makes that decision depend on the parsed prefix and a fixed number of upcoming terminal symbols. Knuth organizes the relevant configurations into finite state sets and a stack recognizer, while explicitly noting potentially large state collections. Prior precedence/bounded-context work and later compact parser generators remain separately attributed.\n\n## Scientific scope\n\nThe LR(k) condition belongs to a grammar with specified lookahead k; two grammars for the same language may differ. Linear parsing claims concern input length for a fixed grammar/parser, and do not bound parser-construction cost or table size. Not all context-free grammars qualify. The whole deterministic-language and unspecified-lookahead undecidability proofs are outside this selected reading.\n\n## People and systems\n\nDonald E. Knuth\n\n\n\n## Original sources\n\n- [Donald E. Knuth, On the Translation of Languages from Left to Right, Information and Control 8(6) (1965), 607–639](https://harrymoreno.com/assets/greatPapersInCompSci/2.5_-_On_the_translation_of_languages_from_left_to_right-Donald_E._Knuth.pdf)\n",
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