Generating flex Lexical Scanners for Perl Parse: : Yapp
نویسندگان
چکیده
Perl is known for its versatile regular expressions. Nevertheless, using Perl regular expressions for creating fast lexical analyzer is not easy. As an alternative, the authors defend the automated generation of the lexical analyzer in a well known fast application (flex) based on a simple Perl definition in the syntactic analyzer. In this paper we extend the syntax used by Parse::Yapp, one of the most used parser generators for Perl, making the automatic generation of flex lexical scanners possible. We explain how this is performed and conclude with some benchmarks that show the relevance of the approach. 1998 ACM Subject Classification D.3.4 Processors
منابع مشابه
Fast parsers for Entrez Gene
NCBI completed the transition of its main genome annotation database from Locuslink to Entrez Gene in Spring 2005. However, to this date few parsers exist for the Entrez Gene annotation file. Owing to the widespread use of Locuslink and the popularity of Perl programming language in bioinformatics, a publicly available high performance Entrez Gene parser in Perl is urgently needed. We present f...
متن کاملParsing Strings and Trees with Parse::Eyapp (An Introduction to Compiler Construction)
Parse::Eyapp (Extended yapp) is a collection of modules that extends Francois Desarmenien Parse::Yapp 1.05. Eyapp extends yacc/yapp syntax with functionalities like named attributes, EBNF-like expressions, modifiable default action, automatic syntax tree building, semi-automatic abstract syntax tree building, translation schemes, tree regular expressions, tree transformations, scope analysis su...
متن کاملComparison of LVG and MetaMap Functionality
LVG and MetaMap both compute lexical variants but were developed for quite different purposes: LVG’s raison d’être is lexical variant generation whereas MetaMap’s main purpose is to map text to corresponding concepts in the UMLS® Metathesaurus (Meta), one of the UMLS knowledge sources. Besides generating lexical variants, LVG has the subsumed ability to normalize words and the supplementary abi...
متن کاملParse Reranking Based on Higher-Order Lexical Dependencies
Existing work shows that lexical dependencies are helpful for constituent tree parsing. However, only first-order lexical dependencies have been employed and investigated in previous work. In this paper, we propose a method to employing higher-order lexical dependencies for constituent tree evaluation. Our method is based on a parse reranking framework, which provides a constrained search space...
متن کاملSemantically Relatable Sets: Building Blocks for Representing Semantics
Motivated by the fact that automatic analysis of language crucially depends on semantic constituent detection and attachment resolution, we present our work on the problem of generating and linking semantically relatable sets (SRS). These sets are of the form or or , where the entities can be single words or more complex se...
متن کامل