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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 : Distribution.Simple.PreProcess.Unlit</span>
<a name="line-4"></a><span class='hs-comment'>-- Copyright : ...</span>
<a name="line-5"></a><span class='hs-comment'>--</span>
<a name="line-6"></a><span class='hs-comment'>-- Maintainer : cabal-devel@haskell.org</span>
<a name="line-7"></a><span class='hs-comment'>-- Portability : portable</span>
<a name="line-8"></a><span class='hs-comment'>--</span>
<a name="line-9"></a><span class='hs-comment'>-- Remove the \"literal\" markups from a Haskell source file, including</span>
<a name="line-10"></a><span class='hs-comment'>-- \"@>@\", \"@\\begin{code}@\", \"@\\end{code}@\", and \"@#@\"</span>
<a name="line-11"></a>
<a name="line-12"></a><span class='hs-comment'>-- This version is interesting because instead of striping comment lines, it</span>
<a name="line-13"></a><span class='hs-comment'>-- turns them into "-- " style comments. This allows using haddock markup</span>
<a name="line-14"></a><span class='hs-comment'>-- in literate scripts without having to use "> --" prefix.</span>
<a name="line-15"></a>
<a name="line-16"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Distribution</span><span class='hs-varop'>.</span><span class='hs-conid'>Simple</span><span class='hs-varop'>.</span><span class='hs-conid'>PreProcess</span><span class='hs-varop'>.</span><span class='hs-conid'>Unlit</span> <span class='hs-layout'>(</span><span class='hs-varid'>unlit</span><span class='hs-layout'>,</span><span class='hs-varid'>plain</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-17"></a>
<a name="line-18"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Char</span>
<a name="line-19"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span>
<a name="line-20"></a>
<a name="line-21"></a><a name="Classified"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Classified</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BirdTrack</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Blank</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Ordinary</span> <span class='hs-conid'>String</span>
<a name="line-22"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Line</span> <span class='hs-varop'>!</span><span class='hs-conid'>Int</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>CPP</span> <span class='hs-conid'>String</span>
<a name="line-23"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>BeginCode</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>EndCode</span>
<a name="line-24"></a> <span class='hs-comment'>-- output only:</span>
<a name="line-25"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Error</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Comment</span> <span class='hs-conid'>String</span>
<a name="line-26"></a>
<a name="line-27"></a><a name="plain"></a><span class='hs-comment'>-- | No unliteration.</span>
<a name="line-28"></a><span class='hs-definition'>plain</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span>
<a name="line-29"></a><span class='hs-definition'>plain</span> <span class='hs-keyword'>_</span> <span class='hs-varid'>hs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>hs</span>
<a name="line-30"></a>
<a name="line-31"></a><a name="classify"></a><span class='hs-definition'>classify</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Classified</span>
<a name="line-32"></a><span class='hs-definition'>classify</span> <span class='hs-layout'>(</span><span class='hs-chr'>'>'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BirdTrack</span> <span class='hs-varid'>s</span>
<a name="line-33"></a><span class='hs-definition'>classify</span> <span class='hs-layout'>(</span><span class='hs-chr'>'#'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>tokens</span> <span class='hs-varid'>s</span> <span class='hs-keyword'>of</span>
<a name="line-34"></a> <span class='hs-layout'>(</span><span class='hs-varid'>line</span><span class='hs-conop'>:</span><span class='hs-varid'>file</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>all</span> <span class='hs-varid'>isDigit</span> <span class='hs-varid'>line</span>
<a name="line-35"></a> <span class='hs-varop'>&&</span> <span class='hs-varid'>length</span> <span class='hs-varid'>file</span> <span class='hs-varop'>>=</span> <span class='hs-num'>2</span>
<a name="line-36"></a> <span class='hs-varop'>&&</span> <span class='hs-varid'>head</span> <span class='hs-varid'>file</span> <span class='hs-varop'>==</span> <span class='hs-chr'>'"'</span>
<a name="line-37"></a> <span class='hs-varop'>&&</span> <span class='hs-varid'>last</span> <span class='hs-varid'>file</span> <span class='hs-varop'>==</span> <span class='hs-chr'>'"'</span>
<a name="line-38"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Line</span> <span class='hs-layout'>(</span><span class='hs-varid'>read</span> <span class='hs-varid'>line</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>tail</span> <span class='hs-layout'>(</span><span class='hs-varid'>init</span> <span class='hs-varid'>file</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-39"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>CPP</span> <span class='hs-varid'>s</span>
<a name="line-40"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>tokens</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>unfoldr</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>str</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>case</span> <span class='hs-varid'>lex</span> <span class='hs-varid'>str</span> <span class='hs-keyword'>of</span>
<a name="line-41"></a> <span class='hs-layout'>(</span><span class='hs-varid'>t</span><span class='hs-keyglyph'>@</span><span class='hs-layout'>(</span><span class='hs-keyword'>_</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>str'</span><span class='hs-layout'>)</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Just</span> <span class='hs-layout'>(</span><span class='hs-varid'>t</span><span class='hs-layout'>,</span> <span class='hs-varid'>str'</span><span class='hs-layout'>)</span>
<a name="line-42"></a> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Nothing</span>
<a name="line-43"></a><span class='hs-definition'>classify</span> <span class='hs-layout'>(</span><span class='hs-chr'>'\\'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span>
<a name="line-44"></a> <span class='hs-keyglyph'>|</span> <span class='hs-str'>"begin{code}"</span> <span class='hs-varop'>`isPrefixOf`</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BeginCode</span>
<a name="line-45"></a> <span class='hs-keyglyph'>|</span> <span class='hs-str'>"end{code}"</span> <span class='hs-varop'>`isPrefixOf`</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>EndCode</span>
<a name="line-46"></a><span class='hs-definition'>classify</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>all</span> <span class='hs-varid'>isSpace</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-varid'>s</span>
<a name="line-47"></a><span class='hs-definition'>classify</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Ordinary</span> <span class='hs-varid'>s</span>
<a name="line-48"></a>
<a name="line-49"></a><a name="unclassify"></a><span class='hs-comment'>-- So the weird exception for comment indenting is to make things work with</span>
<a name="line-50"></a><span class='hs-comment'>-- haddock, see classifyAndCheckForBirdTracks below.</span>
<a name="line-51"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Bool</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Classified</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span>
<a name="line-52"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>BirdTrack</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-chr'>' '</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span>
<a name="line-53"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>Blank</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>s</span>
<a name="line-54"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ordinary</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>s</span>
<a name="line-55"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>Line</span> <span class='hs-varid'>n</span> <span class='hs-varid'>file</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"# "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>show</span> <span class='hs-varid'>n</span> <span class='hs-varop'>++</span> <span class='hs-str'>" "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>show</span> <span class='hs-varid'>file</span>
<a name="line-56"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>CPP</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-chr'>'#'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span>
<a name="line-57"></a><span class='hs-definition'>unclassify</span> <span class='hs-conid'>True</span> <span class='hs-layout'>(</span><span class='hs-conid'>Comment</span> <span class='hs-str'>""</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>" --"</span>
<a name="line-58"></a><span class='hs-definition'>unclassify</span> <span class='hs-conid'>True</span> <span class='hs-layout'>(</span><span class='hs-conid'>Comment</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>" -- "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>s</span>
<a name="line-59"></a><span class='hs-definition'>unclassify</span> <span class='hs-conid'>False</span> <span class='hs-layout'>(</span><span class='hs-conid'>Comment</span> <span class='hs-str'>""</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"--"</span>
<a name="line-60"></a><span class='hs-definition'>unclassify</span> <span class='hs-conid'>False</span> <span class='hs-layout'>(</span><span class='hs-conid'>Comment</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>"-- "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>s</span>
<a name="line-61"></a><span class='hs-definition'>unclassify</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>internalError</span>
<a name="line-62"></a>
<a name="line-63"></a><a name="unlit"></a><span class='hs-comment'>-- | 'unlit' takes a filename (for error reports), and transforms the</span>
<a name="line-64"></a><span class='hs-comment'>-- given string, to eliminate the literate comments from the program text.</span>
<a name="line-65"></a><span class='hs-definition'>unlit</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>FilePath</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Either</span> <span class='hs-conid'>String</span> <span class='hs-conid'>String</span>
<a name="line-66"></a><span class='hs-definition'>unlit</span> <span class='hs-varid'>file</span> <span class='hs-varid'>input</span> <span class='hs-keyglyph'>=</span>
<a name="line-67"></a> <span class='hs-keyword'>let</span> <span class='hs-layout'>(</span><span class='hs-varid'>usesBirdTracks</span><span class='hs-layout'>,</span> <span class='hs-varid'>classified</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>classifyAndCheckForBirdTracks</span>
<a name="line-68"></a> <span class='hs-varop'>.</span> <span class='hs-varid'>inlines</span>
<a name="line-69"></a> <span class='hs-varop'>$</span> <span class='hs-varid'>input</span>
<a name="line-70"></a> <span class='hs-keyword'>in</span> <span class='hs-varid'>either</span> <span class='hs-layout'>(</span><span class='hs-conid'>Left</span> <span class='hs-varop'>.</span> <span class='hs-varid'>unlines</span> <span class='hs-varop'>.</span> <span class='hs-varid'>map</span> <span class='hs-layout'>(</span><span class='hs-varid'>unclassify</span> <span class='hs-varid'>usesBirdTracks</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-71"></a> <span class='hs-conid'>Right</span>
<a name="line-72"></a> <span class='hs-varop'>.</span> <span class='hs-varid'>checkErrors</span>
<a name="line-73"></a> <span class='hs-varop'>.</span> <span class='hs-varid'>reclassify</span>
<a name="line-74"></a> <span class='hs-varop'>$</span> <span class='hs-varid'>classified</span>
<a name="line-75"></a>
<a name="line-76"></a> <span class='hs-keyword'>where</span>
<a name="line-77"></a> <span class='hs-comment'>-- So haddock requires comments and code to align, since it treats comments</span>
<a name="line-78"></a> <span class='hs-comment'>-- as following the layout rule. This is a pain for us since bird track</span>
<a name="line-79"></a> <span class='hs-comment'>-- style literate code typically gets indented by two since ">" is replaced</span>
<a name="line-80"></a> <span class='hs-comment'>-- by " " and people usually use one additional space of indent ie</span>
<a name="line-81"></a> <span class='hs-comment'>-- "> then the code". On the other hand we cannot just go and indent all</span>
<a name="line-82"></a> <span class='hs-comment'>-- the comments by two since that does not work for latex style literate</span>
<a name="line-83"></a> <span class='hs-comment'>-- code. So the hacky solution we use here is that if we see any bird track</span>
<a name="line-84"></a> <span class='hs-comment'>-- style code then we'll indent all comments by two, otherwise by none.</span>
<a name="line-85"></a> <span class='hs-comment'>-- Of course this will not work for mixed latex/bird track .lhs files but</span>
<a name="line-86"></a> <span class='hs-comment'>-- nobody does that, it's silly and specifically recommended against in the</span>
<a name="line-87"></a> <span class='hs-comment'>-- H98 unlit spec.</span>
<a name="line-88"></a> <span class='hs-comment'>--</span>
<a name="line-89"></a> <span class='hs-varid'>classifyAndCheckForBirdTracks</span> <span class='hs-keyglyph'>=</span>
<a name="line-90"></a> <span class='hs-varid'>flip</span> <span class='hs-varid'>mapAccumL</span> <span class='hs-conid'>False</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>seenBirdTrack</span> <span class='hs-varid'>line</span> <span class='hs-keyglyph'>-></span>
<a name="line-91"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>classification</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>classify</span> <span class='hs-varid'>line</span>
<a name="line-92"></a> <span class='hs-keyword'>in</span> <span class='hs-layout'>(</span><span class='hs-varid'>seenBirdTrack</span> <span class='hs-varop'>||</span> <span class='hs-varid'>isBirdTrack</span> <span class='hs-varid'>classification</span><span class='hs-layout'>,</span> <span class='hs-varid'>classification</span><span class='hs-layout'>)</span>
<a name="line-93"></a>
<a name="line-94"></a> <span class='hs-varid'>isBirdTrack</span> <span class='hs-layout'>(</span><span class='hs-conid'>BirdTrack</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>True</span>
<a name="line-95"></a> <span class='hs-varid'>isBirdTrack</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>False</span>
<a name="line-96"></a>
<a name="line-97"></a> <span class='hs-varid'>checkErrors</span> <span class='hs-varid'>ls</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-keyglyph'>[</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Error</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>ls</span> <span class='hs-keyglyph'>]</span> <span class='hs-keyword'>of</span>
<a name="line-98"></a> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Left</span> <span class='hs-varid'>ls</span>
<a name="line-99"></a> <span class='hs-layout'>(</span><span class='hs-varid'>message</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Right</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varop'>++</span> <span class='hs-str'>":"</span> <span class='hs-varop'>++</span> <span class='hs-varid'>show</span> <span class='hs-varid'>n</span> <span class='hs-varop'>++</span> <span class='hs-str'>": "</span> <span class='hs-varop'>++</span> <span class='hs-varid'>message</span><span class='hs-layout'>)</span>
<a name="line-100"></a> <span class='hs-keyword'>where</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span><span class='hs-layout'>,</span> <span class='hs-varid'>n</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>errorPos</span> <span class='hs-varid'>file</span> <span class='hs-num'>1</span> <span class='hs-varid'>ls</span>
<a name="line-101"></a> <span class='hs-varid'>errorPos</span> <span class='hs-varid'>f</span> <span class='hs-varid'>n</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span><span class='hs-layout'>,</span> <span class='hs-varid'>n</span><span class='hs-layout'>)</span>
<a name="line-102"></a> <span class='hs-varid'>errorPos</span> <span class='hs-varid'>f</span> <span class='hs-varid'>n</span> <span class='hs-layout'>(</span><span class='hs-conid'>Error</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span><span class='hs-layout'>,</span> <span class='hs-varid'>n</span><span class='hs-layout'>)</span>
<a name="line-103"></a> <span class='hs-varid'>errorPos</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>Line</span> <span class='hs-varid'>n'</span> <span class='hs-varid'>f'</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>errorPos</span> <span class='hs-varid'>f'</span> <span class='hs-varid'>n'</span> <span class='hs-varid'>ls</span>
<a name="line-104"></a> <span class='hs-varid'>errorPos</span> <span class='hs-varid'>f</span> <span class='hs-varid'>n</span> <span class='hs-layout'>(</span><span class='hs-keyword'>_</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>errorPos</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-varid'>n</span><span class='hs-varop'>+</span><span class='hs-num'>1</span><span class='hs-layout'>)</span> <span class='hs-varid'>ls</span>
<a name="line-105"></a>
<a name="line-106"></a><a name="reclassify"></a><span class='hs-comment'>-- Here we model a state machine, with each state represented by</span>
<a name="line-107"></a><span class='hs-comment'>-- a local function. We only have four states (well, five,</span>
<a name="line-108"></a><span class='hs-comment'>-- if you count the error state), but the rules</span>
<a name="line-109"></a><span class='hs-comment'>-- to transition between then are not so simple.</span>
<a name="line-110"></a><span class='hs-comment'>-- Would it be simpler to have more states?</span>
<a name="line-111"></a><span class='hs-comment'>--</span>
<a name="line-112"></a><span class='hs-comment'>-- Each state represents the type of line that was last read</span>
<a name="line-113"></a><span class='hs-comment'>-- i.e. are we in a comment section, or a latex-code section,</span>
<a name="line-114"></a><span class='hs-comment'>-- or a bird-code section, etc?</span>
<a name="line-115"></a><span class='hs-definition'>reclassify</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Classified</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Classified</span><span class='hs-keyglyph'>]</span>
<a name="line-116"></a><span class='hs-definition'>reclassify</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>blank</span> <span class='hs-comment'>-- begin in blank state</span>
<a name="line-117"></a> <span class='hs-keyword'>where</span>
<a name="line-118"></a> <span class='hs-varid'>latex</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-119"></a> <span class='hs-varid'>latex</span> <span class='hs-layout'>(</span><span class='hs-conid'>EndCode</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-str'>""</span> <span class='hs-conop'>:</span> <span class='hs-varid'>comment</span> <span class='hs-varid'>ls</span>
<a name="line-120"></a> <span class='hs-varid'>latex</span> <span class='hs-layout'>(</span><span class='hs-conid'>BeginCode</span> <span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Error</span> <span class='hs-str'>"\\begin{code} in code section"</span><span class='hs-keyglyph'>]</span>
<a name="line-121"></a> <span class='hs-varid'>latex</span> <span class='hs-layout'>(</span><span class='hs-conid'>BirdTrack</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Ordinary</span> <span class='hs-layout'>(</span><span class='hs-chr'>'>'</span><span class='hs-conop'>:</span><span class='hs-varid'>l</span><span class='hs-layout'>)</span> <span class='hs-conop'>:</span> <span class='hs-varid'>latex</span> <span class='hs-varid'>ls</span>
<a name="line-122"></a> <span class='hs-varid'>latex</span> <span class='hs-layout'>(</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>latex</span> <span class='hs-varid'>ls</span>
<a name="line-123"></a>
<a name="line-124"></a> <span class='hs-varid'>blank</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-125"></a> <span class='hs-varid'>blank</span> <span class='hs-layout'>(</span><span class='hs-conid'>EndCode</span> <span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Error</span> <span class='hs-str'>"\\end{code} without \\begin{code}"</span><span class='hs-keyglyph'>]</span>
<a name="line-126"></a> <span class='hs-varid'>blank</span> <span class='hs-layout'>(</span><span class='hs-conid'>BeginCode</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-str'>""</span> <span class='hs-conop'>:</span> <span class='hs-varid'>latex</span> <span class='hs-varid'>ls</span>
<a name="line-127"></a> <span class='hs-varid'>blank</span> <span class='hs-layout'>(</span><span class='hs-conid'>BirdTrack</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>BirdTrack</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>bird</span> <span class='hs-varid'>ls</span>
<a name="line-128"></a> <span class='hs-varid'>blank</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ordinary</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Comment</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>comment</span> <span class='hs-varid'>ls</span>
<a name="line-129"></a> <span class='hs-varid'>blank</span> <span class='hs-layout'>(</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>blank</span> <span class='hs-varid'>ls</span>
<a name="line-130"></a>
<a name="line-131"></a> <span class='hs-varid'>bird</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-132"></a> <span class='hs-varid'>bird</span> <span class='hs-layout'>(</span><span class='hs-conid'>EndCode</span> <span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Error</span> <span class='hs-str'>"\\end{code} without \\begin{code}"</span><span class='hs-keyglyph'>]</span>
<a name="line-133"></a> <span class='hs-varid'>bird</span> <span class='hs-layout'>(</span><span class='hs-conid'>BeginCode</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-str'>""</span> <span class='hs-conop'>:</span> <span class='hs-varid'>latex</span> <span class='hs-varid'>ls</span>
<a name="line-134"></a> <span class='hs-varid'>bird</span> <span class='hs-layout'>(</span><span class='hs-conid'>Blank</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>blank</span> <span class='hs-varid'>ls</span>
<a name="line-135"></a> <span class='hs-varid'>bird</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ordinary</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Error</span> <span class='hs-str'>"program line before comment line"</span><span class='hs-keyglyph'>]</span>
<a name="line-136"></a> <span class='hs-varid'>bird</span> <span class='hs-layout'>(</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>bird</span> <span class='hs-varid'>ls</span>
<a name="line-137"></a>
<a name="line-138"></a> <span class='hs-varid'>comment</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-139"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>EndCode</span> <span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Error</span> <span class='hs-str'>"\\end{code} without \\begin{code}"</span><span class='hs-keyglyph'>]</span>
<a name="line-140"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>BeginCode</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-str'>""</span> <span class='hs-conop'>:</span> <span class='hs-varid'>latex</span> <span class='hs-varid'>ls</span>
<a name="line-141"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>CPP</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>CPP</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>comment</span> <span class='hs-varid'>ls</span>
<a name="line-142"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>BirdTrack</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span> <span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Error</span> <span class='hs-str'>"comment line before program line"</span><span class='hs-keyglyph'>]</span>
<a name="line-143"></a> <span class='hs-comment'>-- a blank line and another ordinary line following a comment</span>
<a name="line-144"></a> <span class='hs-comment'>-- will be treated as continuing the comment. Otherwise it's</span>
<a name="line-145"></a> <span class='hs-comment'>-- then end of the comment, with a blank line.</span>
<a name="line-146"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>Blank</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-keyglyph'>@</span><span class='hs-layout'>(</span><span class='hs-conid'>Ordinary</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Comment</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>comment</span> <span class='hs-varid'>ls</span>
<a name="line-147"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>Blank</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Blank</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>blank</span> <span class='hs-varid'>ls</span>
<a name="line-148"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>Line</span> <span class='hs-varid'>n</span> <span class='hs-varid'>f</span> <span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Line</span> <span class='hs-varid'>n</span> <span class='hs-varid'>f</span> <span class='hs-conop'>:</span> <span class='hs-varid'>comment</span> <span class='hs-varid'>ls</span>
<a name="line-149"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>Ordinary</span> <span class='hs-varid'>l</span><span class='hs-conop'>:</span><span class='hs-varid'>ls</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Comment</span> <span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>comment</span> <span class='hs-varid'>ls</span>
<a name="line-150"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>Comment</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>internalError</span>
<a name="line-151"></a> <span class='hs-varid'>comment</span> <span class='hs-layout'>(</span><span class='hs-conid'>Error</span> <span class='hs-keyword'>_</span><span class='hs-conop'>:</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>internalError</span>
<a name="line-152"></a>
<a name="line-153"></a><a name="inlines"></a><span class='hs-comment'>-- Re-implementation of 'lines', for better efficiency (but decreased laziness).</span>
<a name="line-154"></a><span class='hs-comment'>-- Also, importantly, accepts non-standard DOS and Mac line ending characters.</span>
<a name="line-155"></a><span class='hs-definition'>inlines</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</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-156"></a><span class='hs-definition'>inlines</span> <span class='hs-varid'>xs</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>lines'</span> <span class='hs-varid'>xs</span> <span class='hs-varid'>id</span>
<a name="line-157"></a> <span class='hs-keyword'>where</span>
<a name="line-158"></a> <span class='hs-varid'>lines'</span> <span class='hs-conid'>[]</span> <span class='hs-varid'>acc</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>acc</span> <span class='hs-conid'>[]</span><span class='hs-keyglyph'>]</span>
<a name="line-159"></a> <span class='hs-varid'>lines'</span> <span class='hs-layout'>(</span><span class='hs-chr'>'\^M'</span><span class='hs-conop'>:</span><span class='hs-chr'>'\n'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>acc</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>acc</span> <span class='hs-conid'>[]</span> <span class='hs-conop'>:</span> <span class='hs-varid'>lines'</span> <span class='hs-varid'>s</span> <span class='hs-varid'>id</span> <span class='hs-comment'>-- DOS</span>
<a name="line-160"></a> <span class='hs-varid'>lines'</span> <span class='hs-layout'>(</span><span class='hs-chr'>'\^M'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>acc</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>acc</span> <span class='hs-conid'>[]</span> <span class='hs-conop'>:</span> <span class='hs-varid'>lines'</span> <span class='hs-varid'>s</span> <span class='hs-varid'>id</span> <span class='hs-comment'>-- MacOS</span>
<a name="line-161"></a> <span class='hs-varid'>lines'</span> <span class='hs-layout'>(</span><span class='hs-chr'>'\n'</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>acc</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>acc</span> <span class='hs-conid'>[]</span> <span class='hs-conop'>:</span> <span class='hs-varid'>lines'</span> <span class='hs-varid'>s</span> <span class='hs-varid'>id</span> <span class='hs-comment'>-- Unix</span>
<a name="line-162"></a> <span class='hs-varid'>lines'</span> <span class='hs-layout'>(</span><span class='hs-varid'>c</span><span class='hs-conop'>:</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>acc</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>lines'</span> <span class='hs-varid'>s</span> <span class='hs-layout'>(</span><span class='hs-varid'>acc</span> <span class='hs-varop'>.</span> <span class='hs-layout'>(</span><span class='hs-varid'>c</span><span class='hs-conop'>:</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-163"></a>
<a name="line-164"></a><a name="internalError"></a><span class='hs-definition'>internalError</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>a</span>
<a name="line-165"></a><span class='hs-definition'>internalError</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>error</span> <span class='hs-str'>"unlit: internal error"</span>
</pre></body>
</html>
