• Title/Summary/Keyword: LL(1) parser

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An Improved Incremental LL(1) Parsing Method (개선된 점진적 LL(1) 파싱 방법)

  • Lee, Gyung-Ok
    • Journal of KIISE:Software and Applications
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    • v.37 no.6
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    • pp.486-490
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    • 2010
  • Incremental parsing has been researched in the intention that the parse result of the original string is reused in the parsing of a new string. This paper proposes an improved method of the previous incremental LL(1) parser with nonterminal lookahead symbols. The previous work is time-inefficient because it repeatedly performs unnecessary steps when an error occurs. This paper gives a solution for the problem.

Characterization of LL languages (LL 언어의 특징화)

  • Lee, Gyung-Ok
    • Journal of KIISE:Software and Applications
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    • v.29 no.1_2
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    • pp.126-131
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    • 2002
  • The problem whether a given grammar G generates an LL language or not is investigated in respect of LL transformable grammars. The previous work involves a nondeterministic intricated parser construction for the characterization of LL transformable grammars. The method hence does not give the intuitive understanding of the essence of LL languages. This paper suggests a characterization of LL transformable grammars based on grammatical derivations instead of the complicated parser construction. The new characterization contributes to intuitive understanding of the essence of LL languages.

Computation of Reusable Points in Incremental LL(1) Parsing (점진적 LL(1) 구문분석에서의 재사용 시점의 계산)

  • Lee, Gyung-Ok
    • Journal of KIISE:Software and Applications
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    • v.37 no.11
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    • pp.845-850
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    • 2010
  • Incremental parsing has been developed to reuse the parse result of the original string during the parsing of a new string. The previous incremental LL(1) parsing methods precomputed the reusable point information before parsing and used it during parsing. This paper proposes an efficient reusable point computation by factoring the common part of the computation. The common symbol storing method and the distance storing method were previously suggested to find the reusable point, and by combining the methods, this paper gives the storing method of the distance to common symbols. Based on it, an efficient incremental LL(1) parser is constructed.

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  • 박철희;유재우
    • Communications of the Korean Institute of Information Scientists and Engineers
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    • v.5 no.2
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    • pp.61-84
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    • 1987
  • This paper deals with actual constructions of programs for experiments in several parsers based on the theoritical results of others that represent on of the most fruiful contributions in computer science. Specifically the report deals with (1) a general computer representation of grammar (2) a precedence parser generator, (3) a LL (1) parser generator, (4) a practical SLR (1)/LALR (1) parser generator.

SPDX Parser and Validator for Software Compliance (소프트웨어 컴플라이언스를 위한 SPDX Parser 및 Validator)

  • Yun, Ho-Yeong;Joe, Yong-Joon;Jung, Byung-Ok;Shin, Dong-Myung
    • Journal of Software Assessment and Valuation
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    • v.13 no.1
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    • pp.15-21
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    • 2017
  • Analyzing a software package which is consisted of big numbers of files takes enormous costs and time. Therefore, SPDX (Software Package Data Exchange) working group collaborate with Linux Foundation published a software information(metadata) specification: SPDX. On the first half of 2017, the specification contains seven chapters and 66 items, according to Ver 2.1 of SPDX spec. It prefers Tag/Value or RDF forms but also supports spreadsheet form. In this paper, we introduce SPDX parsing & validation tools to check the validity of SPDX document. We'll develop SPDX document generator to manage software package more efficiently for our next target.