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On context-free programmed grammars
Computer Languages, 1989Abstract We develop a definition of a deterministic and decidable class of context-free programmed grammars, the SPG class. A table-driven parsing algorithm that operates in quadratic time and an algorithm to produce the parsing table from a given grammar are included.
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Lambek grammars are context free
[1993] Proceedings Eighth Annual IEEE Symposium on Logic in Computer Science, 2002Basic categorial grammars are the context-free ones. Another kind of categorial grammars was introduced by J. Lambek (1958). These grammars are based on a syntactic calculus, known as the Lambek calculus. Chomsky (1963) conjectured that these grammars are also equivalent to context-free ones.
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Acta Informatica, 1994
A text is a triple \(\tau=(\lambda,\rho_ 1,\rho_ 2)\) such that \(\lambda\) is a labeling function, and \(\rho_ 1\) and \(\rho_ 2\) are linear orders on the domain of \(\lambda\); hence \(\tau\) may be seen as a word \((\lambda,\rho_ 1)\) together with an additional linear order \(\rho_ 2\) on the domain of \(\lambda\). The order \(\rho_ 2\) is used to
Andrzej Ehrenfeucht +2 more
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A text is a triple \(\tau=(\lambda,\rho_ 1,\rho_ 2)\) such that \(\lambda\) is a labeling function, and \(\rho_ 1\) and \(\rho_ 2\) are linear orders on the domain of \(\lambda\); hence \(\tau\) may be seen as a word \((\lambda,\rho_ 1)\) together with an additional linear order \(\rho_ 2\) on the domain of \(\lambda\). The order \(\rho_ 2\) is used to
Andrzej Ehrenfeucht +2 more
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PUZZLE GRAMMARS AND CONTEXT-FREE ARRAY GRAMMARS
International Journal of Pattern Recognition and Artificial Intelligence, 1991We introduce a new model for generating finite, digitized, connected pictures called puzzle grammars and study its generative power by comparison with array grammars. We note how this model generalizes the classical Chomskian grammars and study the effect of direction-independent rewriting rules.
Maurice Nivat +4 more
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Attributed Context-Free Hypergraph Grammars
J. Autom. Lang. Comb., 1998Journal of Automata, Languages and Combinatorics, Volume 3, Number 2, 1998, 105 ...
Sebastian Maneth, Heiko Vogler
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Context-free grammars on trees
Proceedings of the first annual ACM symposium on Theory of computing - STOC '69, 1969In this paper we discuss still another version of indexed grammars 1 and macro grammars3,gaining some geometric intuition about the structure of these systems. An ordinary context-free grammar is a rewriting system for strings; we find that a macro grammar is a rewriting system for trees.
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Context-Free Grammars and XML Languages
2006We study the decision properties of XML languages. It was known that given a context-free language included in the Dyck language with sufficiently many pairs of parentheses, it is undecidable whether or not it is an XML language. We improve on this result by showing that the problem remains undecidable when the language is written on a unique pair of ...
A. Bertoni, C. Choffrut, B. Palano
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Defining Contexts in Context-Free Grammars
2012Conjunctive grammars (Okhotin, 2001) are an extension of the standard context-free grammars with a conjunction operation, which maintains most of their practical properties, including many parsing algorithms. This paper introduces a further extension to the model, which is equipped with quantifiers for referring to the left context, in which the ...
Mikhail Barash, Alexander Okhotin
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The Polytope of Context-Free Grammar Constraints
2009Context-free grammar constraints enforce that a sequence of variables forms a word in a language defined by a context-free grammar. The constraint has received a lot of attention in the last few years as it represents an effective and highly expressive modeling entity.
Gilles Pesant +3 more
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Derivatives of Context-free Grammars with Lookahead
Journal of Information Processing, 2023Yasuhiko Minamide
exaly