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MLton
20241230
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<h1>MLLex</h1>
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<div id="preamble">
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<p><a href="#">MLLex</a> is a lexical analyzer generator for <a href="StandardML">Standard ML</a>
modeled after the Lex lexical analyzer generator.</p>
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<p>A version of MLLex, ported from the <a href="SMLNJ">SML/NJ</a> sources, is
distributed with MLton.</p>
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<h2 id="_description">Description</h2>
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<p>MLLex takes as input the lex language as defined in the ML-Lex manual,
and outputs a lexical analyzer in SML.</p>
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<h2 id="_implementation">Implementation</h2>
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<p><a href="https://github.com/MLton/mlton/blob/master/mllex/lexgen.sml"><code>lexgen.sml</code></a></p>
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<p><a href="https://github.com/MLton/mlton/blob/master/mllex/main.sml"><code>main.sml</code></a></p>
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<p><a href="https://github.com/MLton/mlton/blob/master/mllex/call-main.sml"><code>call-main.sml</code></a></p>
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<h2 id="_details_and_notes">Details and Notes</h2>
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<p>There are 3 main passes in the MLLex tool:</p>
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<p>Source parsing. In this pass, lex source program are parsed into internal representations. The core part of this pass is a hand-written lexer and an LL(1) parser. The output of this pass is a record of user code, rules (along with start states) and actions. (MLLex definitions are wiped off.)</p>
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<p>DFA construction. In this pass, a DFA is constructed by the algorithm of H. Yamada et. al.</p>
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<p>Output. In this pass, the generated DFA is written out as a transition table, along with a table-driven algorithm, to an SML file.</p>
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<h2 id="_also_see">Also see</h2>
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<p><a href="Documentation.attachments/mllex.pdf"><code>mllex.pdf</code></a></p>
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<p><a href="MLYacc">MLYacc</a></p>
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<p><a href="References#AppelEtAl94">AppelEtAl94</a></p>
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<p><a href="References#Price09">Price09</a></p>
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Last updated Thu Oct 21 15:53:06 2021 -0400 by Matthew Fluet.
<a href="https://github.com/MLton/mlton/commits/master/doc/guide/src/MLLex.adoc">Log</a>
<a href="https://github.com/MLton/mlton/edit/master/doc/guide/src/MLLex.adoc">Edit</a>
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