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Since the lexical scanning and syntactic parsing are combined, the resulting parser tends to be more complicated and thus harder to understand and debug. The same will hold for the associated grammar, if a grammar is used to generate the
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Dividing processing into a lexer followed by a parser is more modular; scannerless parsing is primarily used when a clear lexer–parser distinction is unneeded or unwanted. Examples of when this is appropriate include
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compiler for writing and implementing compilers. Has token rules as part of its language. Rules in CWIC were compiled into boolean functions returning success or failure.
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The resulting parser tends to be significantly less efficient than a lexer-parser pipeline with regard to both time and memory.
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Laja is a two-phase scannerless parser generator with support for mapping the grammar rules into objects, written in Java.
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This is because parsing at the character level makes the language recognized by the parser a single
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Grammars can be compositional (can be merged without human intervention)
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633:. Lecture Notes in Computer Science. Vol. 5501. pp. 126–141.
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An algorithm that performs tokenization and parsing in a single step
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is scannerless if it uses a single formalism to express both the
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Please help to demonstrate the notability of the topic by citing
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Like META II also is scannerless having builtin lexer functions.
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JSGLR, a pure Java implementation of SGLR, also based on SDF.
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Economopoulos, Giorgios; Klint, Paul; Vinju, Jurgen (2009).
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PyParsing is a scannerless parser written in pure Python.
425:(word level) and phrase level structure of the language.
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allows for both scannerless and scanner-based parsing.
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feature of the general purpose programming language
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675:. The Netherlands: University of Amsterdam.
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184:Relevant discussion may be found on the
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940:Operator-precedence grammar
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246:December 2016
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179:single source
175:This article
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140:December 2016
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82:Please help
77:verification
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898:Memoization
863:Statistical
857:Left corner
814:Generalized
771:Precedence
533:GLR parsers
517:Stratego/XT
285:independent
915:Parse tree
847:Combinator
804:Look-ahead
669:Visser, E.
609:References
453:Advantages
437:grammars,
319:newspapers
293:redirected
216:newspapers
110:newspapers
39:improve it
809:Canonical
764:Bottom-up
677:CiteSeerX
578:TREE-META
462:is needed
458:Only one
439:makefiles
349:June 2023
283:that are
186:talk page
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955:Category
780:Operator
729:Top-down
403:pipeline
572:META II
513:ASF+SDF
494:parser.
433:, most
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645:ISBN
584:CWIC
563:Raku
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447:Raku
435:wiki
417:. A
312:news
209:news
103:news
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431:TeX
389:In
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