Mercurial > repos > deepakjadmin > mayatool3_test3
view mayachemtools/docs/modules/html/SimpleCalcYYLexer.html @ 9:ab29fa5c8c1f draft default tip
Uploaded
| author | deepakjadmin |
|---|---|
| date | Thu, 15 Dec 2016 14:18:03 -0500 |
| parents | 73ae111cf86f |
| children |
line wrap: on
line source
<html> <head> <title>MayaChemTools:Documentation:Parsers::SimpleCalcYYLexer.pm</title> <meta http-equiv="content-type" content="text/html;charset=utf-8"> <link rel="stylesheet" type="text/css" href="../../css/MayaChemTools.css"> </head> <body leftmargin="20" rightmargin="20" topmargin="10" bottommargin="10"> <br/> <center> <a href="http://www.mayachemtools.org" title="MayaChemTools Home"><img src="../../images/MayaChemToolsLogo.gif" border="0" alt="MayaChemTools"></a> </center> <br/> <div class="DocNav"> <table width="100%" border=0 cellpadding=0 cellspacing=2> <tr align="left" valign="top"><td width="33%" align="left"><a href="./SimpleCalcParser.html" title="SimpleCalcParser.html">Previous</a> <a href="./index.html" title="Table of Contents">TOC</a> <a href="./YYLexer.html" title="YYLexer.html">Next</a></td><td width="34%" align="middle"><strong>Parsers::SimpleCalcYYLexer.pm</strong></td><td width="33%" align="right"><a href="././code/SimpleCalcYYLexer.html" title="View source code">Code</a> | <a href="./../pdf/SimpleCalcYYLexer.pdf" title="PDF US Letter Size">PDF</a> | <a href="./../pdfgreen/SimpleCalcYYLexer.pdf" title="PDF US Letter Size with narrow margins: www.changethemargins.com">PDFGreen</a> | <a href="./../pdfa4/SimpleCalcYYLexer.pdf" title="PDF A4 Size">PDFA4</a> | <a href="./../pdfa4green/SimpleCalcYYLexer.pdf" title="PDF A4 Size with narrow margins: www.changethemargins.com">PDFA4Green</a></td></tr> </table> </div> <p> </p> <h2>NAME</h2> <p>Parsers::SimpleCalcYYLexer</p> <p> </p> <h2>SYNOPSIS</h2> <p>use Parsers::SimpleCalcYYLexer;</p> <p>use Parsers::SimpleCalcYYLexer qw(:all);</p> <p> </p> <h2>DESCRIPTION</h2> <p><strong>SimpleCalcYYLexer</strong> class provides the following methods:</p> <p> <a href="#new">new</a>, <a href="#yylex">YYLex</a>, <a href="#getyylex">GetYYLex</a>, <a href="#stringifysimplecalcyylexer">StringifySimpleCalcYYLexer</a> </p><p><strong>Parser::SimpleCalcYYLexer</strong> class is derived from <strong>Parser::YYLexer</strong> class, which in turn is derived from base class <strong>Parser::Lexer</strong> that provides all the underlying lexer functionality. <strong>SimpleCalcYYLexer</strong> class is designed to be used with <strong>yyparse</strong> code generated by running <strong>byacc</strong> on a parser defined using parser definition <strong>SimpleCalcParser.yy</strong> file.</p> <p>The parser package and token table files, <strong>SimpleCalcParser.pm</strong> and <strong>SimpleCalcParser.tab.ph</strong>, are automatically generated from parser grammar definition file, <strong>SimpleCalcParser.yy</strong>, using byacc available through perl-byacc1.8 modified with perl5-byacc-patches-0.5 for generation of object oriented parser:</p> <div class="OptionsBox"> byacc -l -P -d -b SimpleCalcParser SimpleCalcParser.yy <br/> mv SimpleCalcParser.tab.pl SimpleCalcParser.pm</div> <p><strong>SimpleCalcYYLexer.pm</strong> class implements a lexer for a simple calculator and is provided to highlight usasge of <strong>YYLex</strong> through <strong>yyparse</strong>.</p> <p>The default specification of lexer tokens for <strong>SimpleCalcYYLexer.pm</strong> includes:</p> <div class="OptionsBox"> @YYLexerTokensSpec = ( <br/> [ 'LETTER', qr/[a-zA-Z]/ ], [ 'NUMBER', qr/\d+/ ], [ 'SPACE', qr/[ ]*/, <br/> sub { my($This, $TokenLabel, $MatchedText) = @_; return ''; } <br/> ], [ 'NEWLINE', qr/(?:\r\n|\r|\n)/, <br/> sub { my($This, $TokenLabel, $MatchedText) = @_; return "\n"; } <br/> ], [ 'CHAR', qr/./ ] <br/> );</div> <p>The default <strong>SimpleCalcParser.tab.ph</strong> file containing token identifiers for <strong>SimpleCalcParser.yy</strong> includes:</p> <div class="OptionsBox"> $NUMBER=257; <br/> $LETTER=258;</div> <p> </p> <h2>METHODS</h2> <dl> <dt><strong><a name="new" class="item"><strong>new</strong></a></strong></dt> <dd> <div class="OptionsBox"> $SimpleCalcYYLexer = new Parsers::SimpleCalcYYLexer($Input);</div> <p>Using specified <em>Input</em>, <strong>new</strong> method generates a new <strong>SimpleCalcYYLexer</strong> and returns a reference to newly created <strong>SimpleCalcYYLexer</strong> object.</p> <p>Examples:</p> <div class="OptionsBox"> # Input string... <br/> $InputText = "3 + 4 +6\nx=3\ny=5\nx+y\nx+z\n";</div> <div class="OptionsBox"> $YYLexer = new Parsers::SimpleCalcYYLexer($InputText); <br/> $YYLex = $YYLexer->GetYYLex();</div> <div class="OptionsBox"> $Debug = 0; <br/> $CalcParser = new Parsers::SimpleCalcParser($YYLex, \&Parsers::SimpleCalcParser::yyerror, $Debug); <br/> $Value = $SimpleCalcParser->yyparse(); <br/> print "Value: $Value\n";</div> <div class="OptionsBox"> # Input file... <br/> $InputFile = "Input.txt"; <br/> open INPUTFILE, "$InputFile" or die "Couldn't open $InputFile: $!\n"; <br/> $YYLexer = new Parsers::SimpleCalcYYLexer($InputFile); <br/> $YYLex = $YYLexer->GetYYLex();</div> <div class="OptionsBox"> $CalcParser = new Parsers::SimpleCalcParser($YYLex, \&Parsers::SimpleCalcParser::yyerror); <br/> $Value = $SimpleCalcParser->yyparse(); <br/> print "Value: $Value\n";</div> <div class="OptionsBox"> # Input file iterator... <br/> $InputFile = "TestSimpleCalcParser.txt"; <br/> open INPUTFILE, "$InputFile" or die "Couldn't open $InputFile: $!\n"; <br/> $InputIterator = sub { return <INPUTFILE>; }; <br/> $YYLexer = new Parsers::SimpleCalcYYLexer($InputIterator); <br/> $YYLex = $YYLexer->GetYYLex();</div> <div class="OptionsBox"> $CalcParser = new Parsers::SimpleCalcParser($YYLex, \&Parsers::SimpleCalcParser::yyerror); <br/> $Value = $SimpleCalcParser->yyparse(); <br/> print "Value: $Value\n";</div> </dd> <dt><strong><a name="stringifysimplecalcyylexer" class="item"><strong>StringifySimpleCalcYYLexer</strong></a></strong></dt> <dd> <div class="OptionsBox"> $YYLexerString = $YYLexer->StringifySimpleCalcYYLexer();</div> <p>Returns a string containing information about <em>YYLexer</em> object.</p> </dd> </dl> <p> </p> <h2>AUTHOR</h2> <p><a href="mailto:msud@san.rr.com">Manish Sud</a></p> <p> </p> <h2>SEE ALSO</h2> <p><a href="./Lexer.html">Lexer.pm</a>, <a href="./YYLexer.html">YYLexer.pm</a>, <a href="./SimpleCalcParser.html">SimpleCalcParser.yy</a> </p> <p> </p> <h2>COPYRIGHT</h2> <p>Copyright (C) 2015 Manish Sud. All rights reserved.</p> <p>This file is part of MayaChemTools.</p> <p>MayaChemTools is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.</p> <p> </p><p> </p><div class="DocNav"> <table width="100%" border=0 cellpadding=0 cellspacing=2> <tr align="left" valign="top"><td width="33%" align="left"><a href="./SimpleCalcParser.html" title="SimpleCalcParser.html">Previous</a> <a href="./index.html" title="Table of Contents">TOC</a> <a href="./YYLexer.html" title="YYLexer.html">Next</a></td><td width="34%" align="middle"><strong>March 29, 2015</strong></td><td width="33%" align="right"><strong>Parsers::SimpleCalcYYLexer.pm</strong></td></tr> </table> </div> <br /> <center> <img src="../../images/h2o2.png"> </center> </body> </html>