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<pre><a name="line-1"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-2"></a><span class='hs-comment'>-- |</span>
<a name="line-3"></a><span class='hs-comment'>-- Module: Data.Attoparsec.Enumerator</span>
<a name="line-4"></a><span class='hs-comment'>-- Copyright: 2010 John Millikin</span>
<a name="line-5"></a><span class='hs-comment'>-- License: MIT</span>
<a name="line-6"></a><span class='hs-comment'>--</span>
<a name="line-7"></a><span class='hs-comment'>-- Maintainer: jmillikin@gmail.com</span>
<a name="line-8"></a><span class='hs-comment'>-- Portability: portable</span>
<a name="line-9"></a><span class='hs-comment'>--</span>
<a name="line-10"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-11"></a><span class='hs-comment'>{-# LANGUAGE DeriveDataTypeable #-}</span>
<a name="line-12"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Attoparsec</span><span class='hs-varop'>.</span><span class='hs-conid'>Enumerator</span>
<a name="line-13"></a> <span class='hs-layout'>(</span> <span class='hs-conid'>ParseError</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span>
<a name="line-14"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>iterParser</span>
<a name="line-15"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-16"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span> <span class='hs-layout'>(</span><span class='hs-conid'>Exception</span><span class='hs-layout'>)</span>
<a name="line-17"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Typeable</span> <span class='hs-layout'>(</span><span class='hs-conid'>Typeable</span><span class='hs-layout'>)</span>
<a name="line-18"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Attoparsec</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>A</span>
<a name="line-19"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>B</span>
<a name="line-20"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Enumerator</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>E</span>
<a name="line-21"></a>
<a name="line-22"></a><a name="ParseError"></a><span class='hs-comment'>-- | The context and message from a 'A.Fail' value.</span>
<a name="line-23"></a><a name="ParseError"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>ParseError</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>ParseError</span>
<a name="line-24"></a> <span class='hs-layout'>{</span> <span class='hs-varid'>errorContexts</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span>
<a name="line-25"></a> <span class='hs-layout'>,</span> <span class='hs-varid'>errorMessage</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span>
<a name="line-26"></a> <span class='hs-layout'>}</span>
<a name="line-27"></a> <span class='hs-keyword'>deriving</span> <span class='hs-layout'>(</span><span class='hs-conid'>Show</span><span class='hs-layout'>,</span> <span class='hs-conid'>Typeable</span><span class='hs-layout'>)</span>
<a name="line-28"></a>
<a name="line-29"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Exception</span> <span class='hs-conid'>ParseError</span>
<a name="line-30"></a>
<a name="line-31"></a><a name="iterParser"></a><span class='hs-comment'>-- | Convert an Attoparsec 'A.Parser' into an 'E.Iteratee'. The parser will</span>
<a name="line-32"></a><span class='hs-comment'>-- be streamed bytes until it returns 'A.Done' or 'A.Fail'.</span>
<a name="line-33"></a><span class='hs-comment'>--</span>
<a name="line-34"></a><span class='hs-comment'>-- If parsing fails, the iteratee's error value will contain a 'ParseError'.</span>
<a name="line-35"></a><span class='hs-definition'>iterParser</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Monad</span> <span class='hs-varid'>m</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Parser</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-conid'>Iteratee</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-conid'>ByteString</span> <span class='hs-varid'>m</span> <span class='hs-varid'>a</span>
<a name="line-36"></a><span class='hs-definition'>iterParser</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-varid'>continue</span> <span class='hs-layout'>(</span><span class='hs-varid'>step</span> <span class='hs-layout'>(</span><span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-varid'>parse</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-37"></a> <span class='hs-varid'>step</span> <span class='hs-varid'>parse</span> <span class='hs-layout'>(</span><span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-conid'>Chunks</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>parseLoop</span> <span class='hs-varid'>parse</span> <span class='hs-layout'>(</span><span class='hs-varid'>notEmpty</span> <span class='hs-varid'>xs</span><span class='hs-layout'>)</span>
<a name="line-38"></a> <span class='hs-varid'>step</span> <span class='hs-varid'>parse</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-conid'>EOF</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-varid'>feed</span> <span class='hs-layout'>(</span><span class='hs-varid'>parse</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>empty</span><span class='hs-layout'>)</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>empty</span> <span class='hs-keyword'>of</span>
<a name="line-39"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Done</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-varid'>yield</span> <span class='hs-varid'>a</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-conid'>EOF</span>
<a name="line-40"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Partial</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>err</span> <span class='hs-conid'>[]</span> <span class='hs-str'>"iterParser: divergent parser"</span>
<a name="line-41"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Fail</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>ctx</span> <span class='hs-varid'>msg</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>err</span> <span class='hs-varid'>ctx</span> <span class='hs-varid'>msg</span>
<a name="line-42"></a>
<a name="line-43"></a> <span class='hs-varid'>parseLoop</span> <span class='hs-varid'>parse</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-varid'>continue</span> <span class='hs-layout'>(</span><span class='hs-varid'>step</span> <span class='hs-varid'>parse</span><span class='hs-layout'>)</span>
<a name="line-44"></a> <span class='hs-varid'>parseLoop</span> <span class='hs-varid'>parse</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>parse</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>of</span>
<a name="line-45"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Done</span> <span class='hs-varid'>extra</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-varid'>yield</span> <span class='hs-varid'>a</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>if</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>null</span> <span class='hs-varid'>extra</span>
<a name="line-46"></a> <span class='hs-keyword'>then</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-conid'>Chunks</span> <span class='hs-varid'>xs</span>
<a name="line-47"></a> <span class='hs-keyword'>else</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-conid'>Chunks</span> <span class='hs-layout'>(</span><span class='hs-varid'>extra</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span><span class='hs-layout'>)</span>
<a name="line-48"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Partial</span> <span class='hs-varid'>parse'</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>parseLoop</span> <span class='hs-varid'>parse'</span> <span class='hs-varid'>xs</span>
<a name="line-49"></a> <span class='hs-conid'>A</span><span class='hs-varop'>.</span><span class='hs-conid'>Fail</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>ctx</span> <span class='hs-varid'>msg</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>err</span> <span class='hs-varid'>ctx</span> <span class='hs-varid'>msg</span>
<a name="line-50"></a>
<a name="line-51"></a> <span class='hs-varid'>err</span> <span class='hs-varid'>ctx</span> <span class='hs-varid'>msg</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>E</span><span class='hs-varop'>.</span><span class='hs-varid'>throwError</span> <span class='hs-layout'>(</span><span class='hs-conid'>ParseError</span> <span class='hs-varid'>ctx</span> <span class='hs-varid'>msg</span><span class='hs-layout'>)</span>
<a name="line-52"></a> <span class='hs-varid'>notEmpty</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>filter</span> <span class='hs-layout'>(</span><span class='hs-varid'>not</span> <span class='hs-varop'>.</span> <span class='hs-conid'>B</span><span class='hs-varop'>.</span><span class='hs-varid'>null</span><span class='hs-layout'>)</span>
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