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<div><a href="index.html" title="a framework for building parsers">Parsing</a> > <a href="___Analyzer.html" title="the class of all lexical analyzers">Analyzer</a></div>
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<div><h1>Analyzer -- the class of all lexical analyzers</h1>
<div class="single"><h2>Description</h2>
<div><p>A function that accepts input in its original form and separates it into tokens, will be called <span>a <a href="___Analyzer.html">lexical analyzer</a></span>. These analyzers are functional: call one with the original input, and it returns a function of 0 arguments (with changeable internal state) that keeps returning tokens each time it is called until none are left. Actually, the analyzer is to return a pair: <tt>(pos,token)</tt>, where <tt>pos</tt> is a string indicating the position where <tt>token</tt> was found in the input. A position will be a sort of thing which can be converted to string with <a href="../../Macaulay2Doc/html/_to__String.html" title="convert to a string">toString</a> (for printing error messages) and can be sorted.</p>
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<div class="waystouse"><h2>Methods that use a lexical analyzer :</h2>
<ul><li><span><a href="___Parser_sp_co_sp__Analyzer.html" title="combine a parser with a lexical analyzer to make a complete system">Parser : Analyzer</a> -- combine a parser with a lexical analyzer to make a complete system</span></li>
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<h2>Fixed objects of class Analyzer :</h2>
<ul><li><span><a href="_char__Analyzer.html" title="a lexical analyzer that provides characters from a string one at a time">charAnalyzer</a> -- a lexical analyzer that provides characters from a string one at a time</span></li>
<li><span><a href="_nonspace__Analyzer.html" title="a lexical analyzer that provides non-white-space characters from a string one at a time">nonspaceAnalyzer</a> -- a lexical analyzer that provides non-white-space characters from a string one at a time</span></li>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="___Analyzer.html" title="the class of all lexical analyzers">Analyzer</a> is <span>a <a href="../../Macaulay2Doc/html/___Self__Initializing__Type.html">self initializing type</a></span>, with ancestor classes <a href="../../Macaulay2Doc/html/___Function__Closure.html" title="the class of all function closures">FunctionClosure</a> < <a href="../../Macaulay2Doc/html/___Function.html" title="the class of all functions">Function</a> < <a href="../../Macaulay2Doc/html/___Thing.html" title="the class of all things">Thing</a>.</p>
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<div><h3>Menu</h3>
<ul><li><span><a href="_char__Analyzer.html" title="a lexical analyzer that provides characters from a string one at a time">charAnalyzer</a> -- a lexical analyzer that provides characters from a string one at a time</span></li>
<li><span><a href="_nonspace__Analyzer.html" title="a lexical analyzer that provides non-white-space characters from a string one at a time">nonspaceAnalyzer</a> -- a lexical analyzer that provides non-white-space characters from a string one at a time</span></li>
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