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id lex
name Lex
appeared 1975
creators Mike Lesk and Eric Schmidt
tags grammarLanguage
lab https://github.com/babyraging/yash/issues

clocExtensions l lex
fileType text
country United States
reference https://github.com/babyraging/yash

example
 /*** Definition section ***/
 
 %{
 /* C code to be copied verbatim */
 #include <stdio.h>
 %}
 
 %%
     /*** Rules section ***/
 
     /* [0-9]+ matches a string of one or more digits */
 [0-9]+  {
             /* yytext is a string containing the matched text. */
             printf("Saw an integer: %s\n", yytext);
         }
 
 .|\n    {   /* Ignore all other characters. */   }
 
 %%
 /*** C Code section ***/
 
 int main(void)
 {
     /* Call the lexer, then quit. */
     yylex();
     return 0;
 }

lineCommentToken //
multiLineCommentTokens /* */

hasMultiLineComments true
 /* A comment
 */
hasComments true
 /* A comment
 */
hasLineComments true
 // A comment
hasSemanticIndentation false

wikipedia https://en.wikipedia.org/wiki/Lex_(software)
 example
  Saw an integer: 123
  Saw an integer: 2
  Saw an integer: 6
 related yacc unix c regex bison ragel
 summary Lex is a computer program that generates lexical analyzers ("scanners" or "lexers"). Lex is commonly used with the yacc parser generator. Lex, originally written by Mike Lesk and Eric Schmidt and described in 1975, is the standard lexical analyzer generator on many Unix systems, and an equivalent tool is specified as part of the POSIX standard. Lex reads an input stream specifying the lexical analyzer and outputs source code implementing the lexer in the C programming language.
 pageId 105985
 dailyPageViews 178
 created 2002
 backlinksCount 280
 revisionCount 304
 appeared 1975

hopl https://hopl.info/showlanguage.prx?exp=680

githubBigQuery Lex
 repos 12486
 users 9501

linguistGrammarRepo https://github.com/Alhadis/language-grammars
 sampleCount 1
 example
  /*
     +----------------------------------------------------------------------+
     | Zend Engine                                                          |
     +----------------------------------------------------------------------+
     | Copyright (c) 1998-2012 Zend Technologies Ltd. (http://www.zend.com) |
     +----------------------------------------------------------------------+
     | This source file is subject to version 2.00 of the Zend license,     |
     | that is bundled with this package in the file LICENSE, and is        |
     | available through the world-wide-web at the following url:           |
     | http://www.zend.com/license/2_00.txt.                                |
     | If you did not receive a copy of the Zend license and are unable to  |
     | obtain it through the world-wide-web, please send a note to          |
     | license@zend.com so we can mail you a copy immediately.              |
     +----------------------------------------------------------------------+
     | Authors: Zeev Suraski <zeev@zend.com>                                |
     |          Jani Taskinen <jani@php.net>                                |
     |          Marcus Boerger <helly@php.net>                              |
     |          Nuno Lopes <nlopess@php.net>                                |
     |          Scott MacVicar <scottmac@php.net>                           |
     +----------------------------------------------------------------------+
  */
  
  /* $Id$ */
  
  #include <errno.h>
  #include "zend.h"
  #include "zend_globals.h"
  #include <zend_ini_parser.h>
  #include "zend_ini_scanner.h"
  
  #if 0
  # define YYDEBUG(s, c) printf("state: %d char: %c\n", s, c)
  #else
  # define YYDEBUG(s, c)
  #endif
  
  #include "zend_ini_scanner_defs.h"
  
  #define YYCTYPE   unsigned char
  /* allow the scanner to read one null byte after the end of the string (from ZEND_MMAP_AHEAD)
   * so that if will be able to terminate to match the current token (e.g. non-enclosed string) */
  #define YYFILL(n) { if (YYCURSOR > YYLIMIT) return 0

isbndb 2
 year|publisher|title|authors|isbn13
 2012|O’Reilly Media|Lex & Yacc|Doug Brown Doug and John R. Levine and Tony Mason and Tony Mason and Doug Brown|9781449385606
 28-09-2018|Packt Publishing|Hands-On Chatbot Development with Alexa Skills and Amazon Lex|Sam Williams|9781788992435

githubLanguage Lex
 fileExtensions l lex
 trendingProjectsCount 0
 type programming
 filenames Lexer.x lexer.x
 aceMode text
 tmScope source.lex
 aliases flex
 repos 2902