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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<!-- Generated by HsColour, http://code.haskell.org/~malcolm/hscolour/ -->
<title>Distribution/Compat/ReadP.hs</title>
<link type='text/css' rel='stylesheet' href='hscolour.css' />
</head>
<body>
<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.Compat.ReadP</span>
<a name="line-4"></a><span class='hs-comment'>-- Copyright   :  (c) The University of Glasgow 2002</span>
<a name="line-5"></a><span class='hs-comment'>-- License     :  BSD-style (see the file libraries/base/LICENSE)</span>
<a name="line-6"></a><span class='hs-comment'>--</span>
<a name="line-7"></a><span class='hs-comment'>-- Maintainer  :  libraries@haskell.org</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'>-- This is a library of parser combinators, originally written by Koen Claessen.</span>
<a name="line-11"></a><span class='hs-comment'>-- It parses all alternatives in parallel, so it never keeps hold of</span>
<a name="line-12"></a><span class='hs-comment'>-- the beginning of the input string, a common source of space leaks with</span>
<a name="line-13"></a><span class='hs-comment'>-- other parsers.  The '(+++)' choice combinator is genuinely commutative;</span>
<a name="line-14"></a><span class='hs-comment'>-- it makes no difference which branch is \"shorter\".</span>
<a name="line-15"></a><span class='hs-comment'>--</span>
<a name="line-16"></a><span class='hs-comment'>-- See also Koen's paper /Parallel Parsing Processes/</span>
<a name="line-17"></a><span class='hs-comment'>-- (&lt;<a href="http://www.cs.chalmers.se/~koen/publications.html">http://www.cs.chalmers.se/~koen/publications.html</a>&gt;).</span>
<a name="line-18"></a><span class='hs-comment'>--</span>
<a name="line-19"></a><span class='hs-comment'>-- This version of ReadP has been locally hacked to make it H98, by</span>
<a name="line-20"></a><span class='hs-comment'>-- Martin Sj&amp;#xF6;gren &lt;mailto:msjogren@gmail.com&gt;</span>
<a name="line-21"></a><span class='hs-comment'>--</span>
<a name="line-22"></a><span class='hs-comment'>-- The unit tests have been moved to UnitTest.Distribution.Compat.ReadP, by</span>
<a name="line-23"></a><span class='hs-comment'>-- Mark Lentczner &lt;mailto:mark@glyphic.com&gt;</span>
<a name="line-24"></a><span class='hs-comment'>-----------------------------------------------------------------------------</span>
<a name="line-25"></a>
<a name="line-26"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Distribution</span><span class='hs-varop'>.</span><span class='hs-conid'>Compat</span><span class='hs-varop'>.</span><span class='hs-conid'>ReadP</span>
<a name="line-27"></a>  <span class='hs-layout'>(</span>
<a name="line-28"></a>  <span class='hs-comment'>-- * The 'ReadP' type</span>
<a name="line-29"></a>  <span class='hs-conid'>ReadP</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: * -&gt; *; instance Functor, Monad, MonadPlus</span>
<a name="line-30"></a>
<a name="line-31"></a>  <span class='hs-comment'>-- * Primitive operations</span>
<a name="line-32"></a>  <span class='hs-varid'>get</span><span class='hs-layout'>,</span>        <span class='hs-comment'>-- :: ReadP Char</span>
<a name="line-33"></a>  <span class='hs-varid'>look</span><span class='hs-layout'>,</span>       <span class='hs-comment'>-- :: ReadP String</span>
<a name="line-34"></a>  <span class='hs-layout'>(</span><span class='hs-varop'>+++</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: ReadP a -&gt; ReadP a -&gt; ReadP a</span>
<a name="line-35"></a>  <span class='hs-layout'>(</span><span class='hs-varop'>&lt;++</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: ReadP a -&gt; ReadP a -&gt; ReadP a</span>
<a name="line-36"></a>  <span class='hs-varid'>gather</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: ReadP a -&gt; ReadP (String, a)</span>
<a name="line-37"></a>
<a name="line-38"></a>  <span class='hs-comment'>-- * Other operations</span>
<a name="line-39"></a>  <span class='hs-varid'>pfail</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: ReadP a</span>
<a name="line-40"></a>  <span class='hs-varid'>satisfy</span><span class='hs-layout'>,</span>    <span class='hs-comment'>-- :: (Char -&gt; Bool) -&gt; ReadP Char</span>
<a name="line-41"></a>  <span class='hs-varid'>char</span><span class='hs-layout'>,</span>       <span class='hs-comment'>-- :: Char -&gt; ReadP Char</span>
<a name="line-42"></a>  <span class='hs-varid'>string</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: String -&gt; ReadP String</span>
<a name="line-43"></a>  <span class='hs-varid'>munch</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: (Char -&gt; Bool) -&gt; ReadP String</span>
<a name="line-44"></a>  <span class='hs-varid'>munch1</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: (Char -&gt; Bool) -&gt; ReadP String</span>
<a name="line-45"></a>  <span class='hs-varid'>skipSpaces</span><span class='hs-layout'>,</span> <span class='hs-comment'>-- :: ReadP ()</span>
<a name="line-46"></a>  <span class='hs-varid'>choice</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: [ReadP a] -&gt; ReadP a</span>
<a name="line-47"></a>  <span class='hs-varid'>count</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: Int -&gt; ReadP a -&gt; ReadP [a]</span>
<a name="line-48"></a>  <span class='hs-varid'>between</span><span class='hs-layout'>,</span>    <span class='hs-comment'>-- :: ReadP open -&gt; ReadP close -&gt; ReadP a -&gt; ReadP a</span>
<a name="line-49"></a>  <span class='hs-varid'>option</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: a -&gt; ReadP a -&gt; ReadP a</span>
<a name="line-50"></a>  <span class='hs-varid'>optional</span><span class='hs-layout'>,</span>   <span class='hs-comment'>-- :: ReadP a -&gt; ReadP ()</span>
<a name="line-51"></a>  <span class='hs-varid'>many</span><span class='hs-layout'>,</span>       <span class='hs-comment'>-- :: ReadP a -&gt; ReadP [a]</span>
<a name="line-52"></a>  <span class='hs-varid'>many1</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: ReadP a -&gt; ReadP [a]</span>
<a name="line-53"></a>  <span class='hs-varid'>skipMany</span><span class='hs-layout'>,</span>   <span class='hs-comment'>-- :: ReadP a -&gt; ReadP ()</span>
<a name="line-54"></a>  <span class='hs-varid'>skipMany1</span><span class='hs-layout'>,</span>  <span class='hs-comment'>-- :: ReadP a -&gt; ReadP ()</span>
<a name="line-55"></a>  <span class='hs-varid'>sepBy</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: ReadP a -&gt; ReadP sep -&gt; ReadP [a]</span>
<a name="line-56"></a>  <span class='hs-varid'>sepBy1</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: ReadP a -&gt; ReadP sep -&gt; ReadP [a]</span>
<a name="line-57"></a>  <span class='hs-varid'>endBy</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: ReadP a -&gt; ReadP sep -&gt; ReadP [a]</span>
<a name="line-58"></a>  <span class='hs-varid'>endBy1</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: ReadP a -&gt; ReadP sep -&gt; ReadP [a]</span>
<a name="line-59"></a>  <span class='hs-varid'>chainr</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: ReadP a -&gt; ReadP (a -&gt; a -&gt; a) -&gt; a -&gt; ReadP a</span>
<a name="line-60"></a>  <span class='hs-varid'>chainl</span><span class='hs-layout'>,</span>     <span class='hs-comment'>-- :: ReadP a -&gt; ReadP (a -&gt; a -&gt; a) -&gt; a -&gt; ReadP a</span>
<a name="line-61"></a>  <span class='hs-varid'>chainl1</span><span class='hs-layout'>,</span>    <span class='hs-comment'>-- :: ReadP a -&gt; ReadP (a -&gt; a -&gt; a) -&gt; ReadP a</span>
<a name="line-62"></a>  <span class='hs-varid'>chainr1</span><span class='hs-layout'>,</span>    <span class='hs-comment'>-- :: ReadP a -&gt; ReadP (a -&gt; a -&gt; a) -&gt; ReadP a</span>
<a name="line-63"></a>  <span class='hs-varid'>manyTill</span><span class='hs-layout'>,</span>   <span class='hs-comment'>-- :: ReadP a -&gt; ReadP end -&gt; ReadP [a]</span>
<a name="line-64"></a>
<a name="line-65"></a>  <span class='hs-comment'>-- * Running a parser</span>
<a name="line-66"></a>  <span class='hs-conid'>ReadS</span><span class='hs-layout'>,</span>      <span class='hs-comment'>-- :: *; = String -&gt; [(a,String)]</span>
<a name="line-67"></a>  <span class='hs-varid'>readP_to_S</span><span class='hs-layout'>,</span> <span class='hs-comment'>-- :: ReadP a -&gt; ReadS a</span>
<a name="line-68"></a>  <span class='hs-varid'>readS_to_P</span>  <span class='hs-comment'>-- :: ReadS a -&gt; ReadP a</span>
<a name="line-69"></a>  <span class='hs-layout'>)</span>
<a name="line-70"></a> <span class='hs-keyword'>where</span>
<a name="line-71"></a>
<a name="line-72"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span><span class='hs-layout'>(</span> <span class='hs-conid'>MonadPlus</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>liftM</span><span class='hs-layout'>,</span> <span class='hs-varid'>liftM2</span><span class='hs-layout'>,</span> <span class='hs-varid'>ap</span> <span class='hs-layout'>)</span>
<a name="line-73"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Char</span> <span class='hs-layout'>(</span><span class='hs-varid'>isSpace</span><span class='hs-layout'>)</span>
<a name="line-74"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Applicative</span> <span class='hs-layout'>(</span><span class='hs-conid'>Applicative</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-conid'>Alternative</span><span class='hs-layout'>(</span><span class='hs-varid'>empty</span><span class='hs-layout'>,</span> <span class='hs-layout'>(</span><span class='hs-varop'>&lt;|&gt;</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-75"></a>
<a name="line-76"></a><span class='hs-keyword'>infixr</span> <span class='hs-num'>5</span> <span class='hs-varop'>+++</span><span class='hs-layout'>,</span> <span class='hs-varop'>&lt;++</span>
<a name="line-77"></a>
<a name="line-78"></a><span class='hs-comment'>-- ---------------------------------------------------------------------------</span>
<a name="line-79"></a><span class='hs-comment'>-- The P type</span>
<a name="line-80"></a><span class='hs-comment'>-- is representation type -- should be kept abstract</span>
<a name="line-81"></a>
<a name="line-82"></a><a name="P"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span>
<a name="line-83"></a>  <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Get</span> <span class='hs-layout'>(</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-84"></a>  <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>s</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-85"></a>  <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Fail</span>
<a name="line-86"></a>  <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Result</span> <span class='hs-varid'>a</span> <span class='hs-layout'>(</span><span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-87"></a>  <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Final</span> <span class='hs-keyglyph'>[</span><span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-layout'>,</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>s</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span><span class='hs-keyglyph'>]</span> <span class='hs-comment'>-- invariant: list is non-empty!</span>
<a name="line-88"></a>
<a name="line-89"></a><span class='hs-comment'>-- Monad, MonadPlus</span>
<a name="line-90"></a>
<a name="line-91"></a><a name="instance%20Functor%20(P%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Functor</span> <span class='hs-layout'>(</span><span class='hs-conid'>P</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-92"></a>  <span class='hs-varid'>fmap</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftM</span>
<a name="line-93"></a>
<a name="line-94"></a><a name="instance%20Applicative%20(P%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Applicative</span> <span class='hs-layout'>(</span><span class='hs-conid'>P</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-95"></a>  <span class='hs-varid'>pure</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span>
<a name="line-96"></a>  <span class='hs-layout'>(</span><span class='hs-varop'>&lt;*&gt;</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>ap</span>
<a name="line-97"></a>
<a name="line-98"></a><a name="instance%20Monad%20(P%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span><span class='hs-conid'>P</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-99"></a>  <span class='hs-varid'>return</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-conid'>Fail</span>
<a name="line-100"></a>
<a name="line-101"></a>  <span class='hs-layout'>(</span><span class='hs-conid'>Get</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>      <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Get</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>c</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f</span> <span class='hs-varid'>c</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span><span class='hs-layout'>)</span>
<a name="line-102"></a>  <span class='hs-layout'>(</span><span class='hs-conid'>Look</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>     <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f</span> <span class='hs-varid'>s</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span><span class='hs-layout'>)</span>
<a name="line-103"></a>  <span class='hs-conid'>Fail</span>         <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Fail</span>
<a name="line-104"></a>  <span class='hs-layout'>(</span><span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>k</span> <span class='hs-varid'>x</span> <span class='hs-varop'>`mplus`</span> <span class='hs-layout'>(</span><span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span><span class='hs-layout'>)</span>
<a name="line-105"></a>  <span class='hs-layout'>(</span><span class='hs-conid'>Final</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span>    <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>k</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>final</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>ys'</span> <span class='hs-keyglyph'>|</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-layout'>,</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>r</span><span class='hs-layout'>,</span> <span class='hs-varid'>ys'</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>k</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span><span class='hs-keyglyph'>]</span>
<a name="line-106"></a>
<a name="line-107"></a>  <span class='hs-varid'>fail</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Fail</span>
<a name="line-108"></a>
<a name="line-109"></a><a name="instance%20Alternative%20(P%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Alternative</span> <span class='hs-layout'>(</span><span class='hs-conid'>P</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-110"></a>      <span class='hs-varid'>empty</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mzero</span>
<a name="line-111"></a>      <span class='hs-layout'>(</span><span class='hs-varop'>&lt;|&gt;</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>mplus</span>
<a name="line-112"></a>
<a name="line-113"></a><a name="instance%20MonadPlus%20(P%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>MonadPlus</span> <span class='hs-layout'>(</span><span class='hs-conid'>P</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-114"></a>  <span class='hs-varid'>mzero</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Fail</span>
<a name="line-115"></a>
<a name="line-116"></a>  <span class='hs-comment'>-- most common case: two gets are combined</span>
<a name="line-117"></a>  <span class='hs-conid'>Get</span> <span class='hs-varid'>f1</span>     <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Get</span> <span class='hs-varid'>f2</span>     <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Get</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>c</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f1</span> <span class='hs-varid'>c</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>f2</span> <span class='hs-varid'>c</span><span class='hs-layout'>)</span>
<a name="line-118"></a>
<a name="line-119"></a>  <span class='hs-comment'>-- results are delivered as soon as possible</span>
<a name="line-120"></a>  <span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-varid'>p</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>q</span>          <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-layout'>(</span><span class='hs-varid'>p</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>q</span><span class='hs-layout'>)</span>
<a name="line-121"></a>  <span class='hs-varid'>p</span>          <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-varid'>q</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-layout'>(</span><span class='hs-varid'>p</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>q</span><span class='hs-layout'>)</span>
<a name="line-122"></a>
<a name="line-123"></a>  <span class='hs-comment'>-- fail disappears</span>
<a name="line-124"></a>  <span class='hs-conid'>Fail</span>       <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>p</span>          <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span>
<a name="line-125"></a>  <span class='hs-varid'>p</span>          <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Fail</span>       <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span>
<a name="line-126"></a>
<a name="line-127"></a>  <span class='hs-comment'>-- two finals are combined</span>
<a name="line-128"></a>  <span class='hs-comment'>-- final + look becomes one look and one final (=optimization)</span>
<a name="line-129"></a>  <span class='hs-comment'>-- final + sthg else becomes one look and one final</span>
<a name="line-130"></a>  <span class='hs-conid'>Final</span> <span class='hs-varid'>r</span>    <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Final</span> <span class='hs-varid'>t</span>    <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Final</span> <span class='hs-layout'>(</span><span class='hs-varid'>r</span> <span class='hs-varop'>++</span> <span class='hs-varid'>t</span><span class='hs-layout'>)</span>
<a name="line-131"></a>  <span class='hs-conid'>Final</span> <span class='hs-varid'>r</span>    <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Look</span> <span class='hs-varid'>f</span>     <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Final</span> <span class='hs-layout'>(</span><span class='hs-varid'>r</span> <span class='hs-varop'>++</span> <span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-132"></a>  <span class='hs-conid'>Final</span> <span class='hs-varid'>r</span>    <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>p</span>          <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Final</span> <span class='hs-layout'>(</span><span class='hs-varid'>r</span> <span class='hs-varop'>++</span> <span class='hs-varid'>run</span> <span class='hs-varid'>p</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-133"></a>  <span class='hs-conid'>Look</span> <span class='hs-varid'>f</span>     <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Final</span> <span class='hs-varid'>r</span>    <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Final</span> <span class='hs-layout'>(</span><span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span> <span class='hs-varop'>++</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-134"></a>  <span class='hs-varid'>p</span>          <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Final</span> <span class='hs-varid'>r</span>    <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Final</span> <span class='hs-layout'>(</span><span class='hs-varid'>run</span> <span class='hs-varid'>p</span> <span class='hs-varid'>s</span> <span class='hs-varop'>++</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-135"></a>
<a name="line-136"></a>  <span class='hs-comment'>-- two looks are combined (=optimization)</span>
<a name="line-137"></a>  <span class='hs-comment'>-- look + sthg else floats upwards</span>
<a name="line-138"></a>  <span class='hs-conid'>Look</span> <span class='hs-varid'>f</span>     <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Look</span> <span class='hs-varid'>g</span>     <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f</span> <span class='hs-varid'>s</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>g</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span>
<a name="line-139"></a>  <span class='hs-conid'>Look</span> <span class='hs-varid'>f</span>     <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>p</span>          <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f</span> <span class='hs-varid'>s</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span>
<a name="line-140"></a>  <span class='hs-varid'>p</span>          <span class='hs-varop'>`mplus`</span> <span class='hs-conid'>Look</span> <span class='hs-varid'>f</span>     <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>p</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>f</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span>
<a name="line-141"></a>
<a name="line-142"></a><span class='hs-comment'>-- ---------------------------------------------------------------------------</span>
<a name="line-143"></a><span class='hs-comment'>-- The ReadP type</span>
<a name="line-144"></a>
<a name="line-145"></a><a name="Parser"></a><span class='hs-keyword'>newtype</span> <span class='hs-conid'>Parser</span> <span class='hs-varid'>r</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span>
<a name="line-146"></a><a name="ReadP"></a><span class='hs-keyword'>type</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Parser</span> <span class='hs-varid'>r</span> <span class='hs-conid'>Char</span> <span class='hs-varid'>a</span>
<a name="line-147"></a>
<a name="line-148"></a><span class='hs-comment'>-- Functor, Monad, MonadPlus</span>
<a name="line-149"></a>
<a name="line-150"></a><a name="instance%20Functor%20(Parser%20r%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Functor</span> <span class='hs-layout'>(</span><span class='hs-conid'>Parser</span> <span class='hs-varid'>r</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-151"></a>  <span class='hs-varid'>fmap</span> <span class='hs-varid'>h</span> <span class='hs-layout'>(</span><span class='hs-conid'>R</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>k</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f</span> <span class='hs-layout'>(</span><span class='hs-varid'>k</span> <span class='hs-varop'>.</span> <span class='hs-varid'>h</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-152"></a>
<a name="line-153"></a><a name="instance%20Applicative%20(Parser%20r%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Applicative</span> <span class='hs-layout'>(</span><span class='hs-conid'>Parser</span> <span class='hs-varid'>r</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-154"></a>  <span class='hs-varid'>pure</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span>
<a name="line-155"></a>  <span class='hs-layout'>(</span><span class='hs-varop'>&lt;*&gt;</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>ap</span>
<a name="line-156"></a>
<a name="line-157"></a><a name="instance%20Monad%20(Parser%20r%20s)"></a><span class='hs-keyword'>instance</span> <span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span><span class='hs-conid'>Parser</span> <span class='hs-varid'>r</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-158"></a>  <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>  <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>k</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>k</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-159"></a>  <span class='hs-varid'>fail</span> <span class='hs-keyword'>_</span>    <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Fail</span><span class='hs-layout'>)</span>
<a name="line-160"></a>  <span class='hs-conid'>R</span> <span class='hs-varid'>m</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>k</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-keyword'>let</span> <span class='hs-conid'>R</span> <span class='hs-varid'>m'</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>f</span> <span class='hs-varid'>a</span> <span class='hs-keyword'>in</span> <span class='hs-varid'>m'</span> <span class='hs-varid'>k</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-161"></a>
<a name="line-162"></a><span class='hs-comment'>--instance MonadPlus (Parser r s) where</span>
<a name="line-163"></a><span class='hs-comment'>--  mzero = pfail</span>
<a name="line-164"></a><span class='hs-comment'>--  mplus = (+++)</span>
<a name="line-165"></a>
<a name="line-166"></a><span class='hs-comment'>-- ---------------------------------------------------------------------------</span>
<a name="line-167"></a><span class='hs-comment'>-- Operations over P</span>
<a name="line-168"></a>
<a name="line-169"></a><a name="final"></a><span class='hs-definition'>final</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-layout'>,</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>s</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>P</span> <span class='hs-varid'>s</span> <span class='hs-varid'>a</span>
<a name="line-170"></a><span class='hs-comment'>-- Maintains invariant for Final constructor</span>
<a name="line-171"></a><span class='hs-definition'>final</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Fail</span>
<a name="line-172"></a><span class='hs-definition'>final</span> <span class='hs-varid'>r</span>  <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Final</span> <span class='hs-varid'>r</span>
<a name="line-173"></a>
<a name="line-174"></a><a name="run"></a><span class='hs-definition'>run</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>P</span> <span class='hs-varid'>c</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>c</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-keyglyph'>[</span><span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>c</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span>
<a name="line-175"></a><span class='hs-definition'>run</span> <span class='hs-layout'>(</span><span class='hs-conid'>Get</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</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-keyglyph'>=</span> <span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>c</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span>
<a name="line-176"></a><span class='hs-definition'>run</span> <span class='hs-layout'>(</span><span class='hs-conid'>Look</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>     <span class='hs-varid'>s</span>     <span class='hs-keyglyph'>=</span> <span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span>
<a name="line-177"></a><span class='hs-definition'>run</span> <span class='hs-layout'>(</span><span class='hs-conid'>Result</span> <span class='hs-varid'>x</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span>     <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-layout'>,</span><span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-conop'>:</span> <span class='hs-varid'>run</span> <span class='hs-varid'>p</span> <span class='hs-varid'>s</span>
<a name="line-178"></a><span class='hs-definition'>run</span> <span class='hs-layout'>(</span><span class='hs-conid'>Final</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span>    <span class='hs-keyword'>_</span>     <span class='hs-keyglyph'>=</span> <span class='hs-varid'>r</span>
<a name="line-179"></a><span class='hs-definition'>run</span> <span class='hs-keyword'>_</span>            <span class='hs-keyword'>_</span>     <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-180"></a>
<a name="line-181"></a><span class='hs-comment'>-- ---------------------------------------------------------------------------</span>
<a name="line-182"></a><span class='hs-comment'>-- Operations over ReadP</span>
<a name="line-183"></a>
<a name="line-184"></a><a name="get"></a><span class='hs-definition'>get</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>Char</span>
<a name="line-185"></a><span class='hs-comment'>-- ^ Consumes and returns the next character.</span>
<a name="line-186"></a><span class='hs-comment'>--   Fails if there is no input left.</span>
<a name="line-187"></a><span class='hs-definition'>get</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-conid'>Get</span>
<a name="line-188"></a>
<a name="line-189"></a><a name="look"></a><span class='hs-definition'>look</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>String</span>
<a name="line-190"></a><span class='hs-comment'>-- ^ Look-ahead: returns the part of the input that is left, without</span>
<a name="line-191"></a><span class='hs-comment'>--   consuming it.</span>
<a name="line-192"></a><span class='hs-definition'>look</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-conid'>Look</span>
<a name="line-193"></a>
<a name="line-194"></a><a name="pfail"></a><span class='hs-definition'>pfail</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-195"></a><span class='hs-comment'>-- ^ Always fails.</span>
<a name="line-196"></a><span class='hs-definition'>pfail</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-keyword'>_</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Fail</span><span class='hs-layout'>)</span>
<a name="line-197"></a>
<a name="line-198"></a><a name="+++"></a><span class='hs-layout'>(</span><span class='hs-varop'>+++</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-199"></a><span class='hs-comment'>-- ^ Symmetric choice.</span>
<a name="line-200"></a><span class='hs-conid'>R</span> <span class='hs-varid'>f1</span> <span class='hs-varop'>+++</span> <span class='hs-conid'>R</span> <span class='hs-varid'>f2</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>k</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>f1</span> <span class='hs-varid'>k</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>f2</span> <span class='hs-varid'>k</span><span class='hs-layout'>)</span>
<a name="line-201"></a>
<a name="line-202"></a><a name="%3c++"></a><span class='hs-layout'>(</span><span class='hs-varop'>&lt;++</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>a</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-203"></a><span class='hs-comment'>-- ^ Local, exclusive, left-biased choice: If left parser</span>
<a name="line-204"></a><span class='hs-comment'>--   locally produces any result at all, then right parser is</span>
<a name="line-205"></a><span class='hs-comment'>--   not used.</span>
<a name="line-206"></a><span class='hs-conid'>R</span> <span class='hs-varid'>f</span> <span class='hs-varop'>&lt;++</span> <span class='hs-varid'>q</span> <span class='hs-keyglyph'>=</span>
<a name="line-207"></a>  <span class='hs-keyword'>do</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>look</span>
<a name="line-208"></a>     <span class='hs-varid'>probe</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>return</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span> <span class='hs-num'>0</span>
<a name="line-209"></a> <span class='hs-keyword'>where</span>
<a name="line-210"></a>  <span class='hs-varid'>probe</span> <span class='hs-layout'>(</span><span class='hs-conid'>Get</span> <span class='hs-varid'>f'</span><span class='hs-layout'>)</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'>n</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>probe</span> <span class='hs-layout'>(</span><span class='hs-varid'>f'</span> <span class='hs-varid'>c</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</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-keyglyph'>::</span> <span class='hs-conid'>Int</span><span class='hs-layout'>)</span>
<a name="line-211"></a>  <span class='hs-varid'>probe</span> <span class='hs-layout'>(</span><span class='hs-conid'>Look</span> <span class='hs-varid'>f'</span><span class='hs-layout'>)</span>      <span class='hs-varid'>s</span>     <span class='hs-varid'>n</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>probe</span> <span class='hs-layout'>(</span><span class='hs-varid'>f'</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span> <span class='hs-varid'>s</span> <span class='hs-varid'>n</span>
<a name="line-212"></a>  <span class='hs-varid'>probe</span> <span class='hs-varid'>p</span><span class='hs-keyglyph'>@</span><span class='hs-layout'>(</span><span class='hs-conid'>Result</span> <span class='hs-keyword'>_</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyword'>_</span>     <span class='hs-varid'>n</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>discard</span> <span class='hs-varid'>n</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;=</span><span class='hs-layout'>)</span>
<a name="line-213"></a>  <span class='hs-varid'>probe</span> <span class='hs-layout'>(</span><span class='hs-conid'>Final</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span>      <span class='hs-keyword'>_</span>     <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-conid'>Final</span> <span class='hs-varid'>r</span> <span class='hs-varop'>&gt;&gt;=</span><span class='hs-layout'>)</span>
<a name="line-214"></a>  <span class='hs-varid'>probe</span> <span class='hs-keyword'>_</span>              <span class='hs-keyword'>_</span>     <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>q</span>
<a name="line-215"></a>
<a name="line-216"></a>  <span class='hs-varid'>discard</span> <span class='hs-num'>0</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-217"></a>  <span class='hs-varid'>discard</span> <span class='hs-varid'>n</span>  <span class='hs-keyglyph'>=</span> <span class='hs-varid'>get</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>discard</span> <span class='hs-layout'>(</span><span class='hs-varid'>n</span><span class='hs-comment'>-</span><span class='hs-num'>1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Int</span><span class='hs-layout'>)</span>
<a name="line-218"></a>
<a name="line-219"></a><a name="gather"></a><span class='hs-definition'>gather</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-layout'>(</span><span class='hs-conid'>String</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>P</span> <span class='hs-conid'>Char</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-layout'>(</span><span class='hs-conid'>String</span><span class='hs-layout'>,</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span>
<a name="line-220"></a><span class='hs-comment'>-- ^ Transforms a parser into one that does the same, but</span>
<a name="line-221"></a><span class='hs-comment'>--   in addition returns the exact characters read.</span>
<a name="line-222"></a><span class='hs-comment'>--   IMPORTANT NOTE: 'gather' gives a runtime error if its first argument</span>
<a name="line-223"></a><span class='hs-comment'>--   is built using any occurrences of readS_to_P.</span>
<a name="line-224"></a><span class='hs-definition'>gather</span> <span class='hs-layout'>(</span><span class='hs-conid'>R</span> <span class='hs-varid'>m</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span>
<a name="line-225"></a>  <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>k</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>gath</span> <span class='hs-varid'>id</span> <span class='hs-layout'>(</span><span class='hs-varid'>m</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>k</span> <span class='hs-layout'>(</span><span class='hs-varid'>s</span><span class='hs-layout'>,</span><span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-226"></a> <span class='hs-keyword'>where</span>
<a name="line-227"></a>  <span class='hs-varid'>gath</span> <span class='hs-varid'>l</span> <span class='hs-layout'>(</span><span class='hs-conid'>Get</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>      <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Get</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>c</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>gath</span> <span class='hs-layout'>(</span><span class='hs-varid'>l</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> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>c</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-228"></a>  <span class='hs-varid'>gath</span> <span class='hs-keyword'>_</span> <span class='hs-conid'>Fail</span>         <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Fail</span>
<a name="line-229"></a>  <span class='hs-varid'>gath</span> <span class='hs-varid'>l</span> <span class='hs-layout'>(</span><span class='hs-conid'>Look</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span>     <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>gath</span> <span class='hs-varid'>l</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>s</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-230"></a>  <span class='hs-varid'>gath</span> <span class='hs-varid'>l</span> <span class='hs-layout'>(</span><span class='hs-conid'>Result</span> <span class='hs-varid'>k</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>k</span> <span class='hs-layout'>(</span><span class='hs-varid'>l</span> <span class='hs-conid'>[]</span><span class='hs-layout'>)</span> <span class='hs-varop'>`mplus`</span> <span class='hs-varid'>gath</span> <span class='hs-varid'>l</span> <span class='hs-varid'>p</span>
<a name="line-231"></a>  <span class='hs-varid'>gath</span> <span class='hs-keyword'>_</span> <span class='hs-layout'>(</span><span class='hs-conid'>Final</span> <span class='hs-keyword'>_</span><span class='hs-layout'>)</span>    <span class='hs-keyglyph'>=</span> <span class='hs-varid'>error</span> <span class='hs-str'>"do not use readS_to_P in gather!"</span>
<a name="line-232"></a>
<a name="line-233"></a><span class='hs-comment'>-- ---------------------------------------------------------------------------</span>
<a name="line-234"></a><span class='hs-comment'>-- Derived operations</span>
<a name="line-235"></a>
<a name="line-236"></a><a name="satisfy"></a><span class='hs-definition'>satisfy</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Bool</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>Char</span>
<a name="line-237"></a><span class='hs-comment'>-- ^ Consumes and returns the next character, if it satisfies the</span>
<a name="line-238"></a><span class='hs-comment'>--   specified predicate.</span>
<a name="line-239"></a><span class='hs-definition'>satisfy</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>get</span><span class='hs-layout'>;</span> <span class='hs-keyword'>if</span> <span class='hs-varid'>p</span> <span class='hs-varid'>c</span> <span class='hs-keyword'>then</span> <span class='hs-varid'>return</span> <span class='hs-varid'>c</span> <span class='hs-keyword'>else</span> <span class='hs-varid'>pfail</span>
<a name="line-240"></a>
<a name="line-241"></a><a name="char"></a><span class='hs-definition'>char</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>Char</span>
<a name="line-242"></a><span class='hs-comment'>-- ^ Parses and returns the specified character.</span>
<a name="line-243"></a><span class='hs-definition'>char</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>satisfy</span> <span class='hs-layout'>(</span><span class='hs-varid'>c</span> <span class='hs-varop'>==</span><span class='hs-layout'>)</span>
<a name="line-244"></a>
<a name="line-245"></a><a name="string"></a><span class='hs-definition'>string</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>String</span>
<a name="line-246"></a><span class='hs-comment'>-- ^ Parses and returns the specified string.</span>
<a name="line-247"></a><span class='hs-definition'>string</span> <span class='hs-varid'>this</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>look</span><span class='hs-layout'>;</span> <span class='hs-varid'>scan</span> <span class='hs-varid'>this</span> <span class='hs-varid'>s</span>
<a name="line-248"></a> <span class='hs-keyword'>where</span>
<a name="line-249"></a>  <span class='hs-varid'>scan</span> <span class='hs-conid'>[]</span>     <span class='hs-keyword'>_</span>               <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>return</span> <span class='hs-varid'>this</span>
<a name="line-250"></a>  <span class='hs-varid'>scan</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-layout'>(</span><span class='hs-varid'>y</span><span class='hs-conop'>:</span><span class='hs-varid'>ys</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>y</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>get</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>scan</span> <span class='hs-varid'>xs</span> <span class='hs-varid'>ys</span>
<a name="line-251"></a>  <span class='hs-varid'>scan</span> <span class='hs-keyword'>_</span>      <span class='hs-keyword'>_</span>               <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>pfail</span>
<a name="line-252"></a>
<a name="line-253"></a><a name="munch"></a><span class='hs-definition'>munch</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Bool</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>String</span>
<a name="line-254"></a><span class='hs-comment'>-- ^ Parses the first zero or more characters satisfying the predicate.</span>
<a name="line-255"></a><span class='hs-definition'>munch</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span>
<a name="line-256"></a>  <span class='hs-keyword'>do</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>look</span>
<a name="line-257"></a>     <span class='hs-varid'>scan</span> <span class='hs-varid'>s</span>
<a name="line-258"></a> <span class='hs-keyword'>where</span>
<a name="line-259"></a>  <span class='hs-varid'>scan</span> <span class='hs-layout'>(</span><span class='hs-varid'>c</span><span class='hs-conop'>:</span><span class='hs-varid'>cs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>|</span> <span class='hs-varid'>p</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>get</span><span class='hs-layout'>;</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>scan</span> <span class='hs-varid'>cs</span><span class='hs-layout'>;</span> <span class='hs-varid'>return</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>
<a name="line-260"></a>  <span class='hs-varid'>scan</span> <span class='hs-keyword'>_</span>            <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>return</span> <span class='hs-str'>""</span>
<a name="line-261"></a>
<a name="line-262"></a><a name="munch1"></a><span class='hs-definition'>munch1</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-conid'>Char</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Bool</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>String</span>
<a name="line-263"></a><span class='hs-comment'>-- ^ Parses the first one or more characters satisfying the predicate.</span>
<a name="line-264"></a><span class='hs-definition'>munch1</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span>
<a name="line-265"></a>  <span class='hs-keyword'>do</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>get</span>
<a name="line-266"></a>     <span class='hs-keyword'>if</span> <span class='hs-varid'>p</span> <span class='hs-varid'>c</span> <span class='hs-keyword'>then</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>munch</span> <span class='hs-varid'>p</span><span class='hs-layout'>;</span> <span class='hs-varid'>return</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>
<a name="line-267"></a>            <span class='hs-keyword'>else</span> <span class='hs-varid'>pfail</span>
<a name="line-268"></a>
<a name="line-269"></a><a name="choice"></a><span class='hs-definition'>choice</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-270"></a><span class='hs-comment'>-- ^ Combines all parsers in the specified list.</span>
<a name="line-271"></a><span class='hs-definition'>choice</span> <span class='hs-conid'>[]</span>     <span class='hs-keyglyph'>=</span> <span class='hs-varid'>pfail</span>
<a name="line-272"></a><span class='hs-definition'>choice</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>p</span><span class='hs-keyglyph'>]</span>    <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span>
<a name="line-273"></a><span class='hs-definition'>choice</span> <span class='hs-layout'>(</span><span class='hs-varid'>p</span><span class='hs-conop'>:</span><span class='hs-varid'>ps</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>choice</span> <span class='hs-varid'>ps</span>
<a name="line-274"></a>
<a name="line-275"></a><a name="skipSpaces"></a><span class='hs-definition'>skipSpaces</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>()</span>
<a name="line-276"></a><span class='hs-comment'>-- ^ Skips all whitespace.</span>
<a name="line-277"></a><span class='hs-definition'>skipSpaces</span> <span class='hs-keyglyph'>=</span>
<a name="line-278"></a>  <span class='hs-keyword'>do</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>look</span>
<a name="line-279"></a>     <span class='hs-varid'>skip</span> <span class='hs-varid'>s</span>
<a name="line-280"></a> <span class='hs-keyword'>where</span>
<a name="line-281"></a>  <span class='hs-varid'>skip</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-keyglyph'>|</span> <span class='hs-varid'>isSpace</span> <span class='hs-varid'>c</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>get</span><span class='hs-layout'>;</span> <span class='hs-varid'>skip</span> <span class='hs-varid'>s</span>
<a name="line-282"></a>  <span class='hs-varid'>skip</span> <span class='hs-keyword'>_</span>                 <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-283"></a>
<a name="line-284"></a><a name="count"></a><span class='hs-definition'>count</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Int</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-285"></a><span class='hs-comment'>-- ^ @ count n p @ parses @n@ occurrences of @p@ in sequence. A list of</span>
<a name="line-286"></a><span class='hs-comment'>--   results is returned.</span>
<a name="line-287"></a><span class='hs-definition'>count</span> <span class='hs-varid'>n</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>sequence</span> <span class='hs-layout'>(</span><span class='hs-varid'>replicate</span> <span class='hs-varid'>n</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span>
<a name="line-288"></a>
<a name="line-289"></a><a name="between"></a><span class='hs-definition'>between</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>open</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>close</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-290"></a><span class='hs-comment'>-- ^ @ between open close p @ parses @open@, followed by @p@ and finally</span>
<a name="line-291"></a><span class='hs-comment'>--   @close@. Only the value of @p@ is returned.</span>
<a name="line-292"></a><span class='hs-definition'>between</span> <span class='hs-varid'>open</span> <span class='hs-varid'>close</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>open</span>
<a name="line-293"></a>                          <span class='hs-varid'>x</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>p</span>
<a name="line-294"></a>                          <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>close</span>
<a name="line-295"></a>                          <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-296"></a>
<a name="line-297"></a><a name="option"></a><span class='hs-definition'>option</span> <span class='hs-keyglyph'>::</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-298"></a><span class='hs-comment'>-- ^ @option x p@ will either parse @p@ or return @x@ without consuming</span>
<a name="line-299"></a><span class='hs-comment'>--   any input.</span>
<a name="line-300"></a><span class='hs-definition'>option</span> <span class='hs-varid'>x</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-301"></a>
<a name="line-302"></a><a name="optional"></a><span class='hs-definition'>optional</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>()</span>
<a name="line-303"></a><span class='hs-comment'>-- ^ @optional p@ optionally parses @p@ and always returns @()@.</span>
<a name="line-304"></a><span class='hs-definition'>optional</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span><span class='hs-layout'>)</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-305"></a>
<a name="line-306"></a><a name="many"></a><span class='hs-definition'>many</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-307"></a><span class='hs-comment'>-- ^ Parses zero or more occurrences of the given parser.</span>
<a name="line-308"></a><span class='hs-definition'>many</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span> <span class='hs-conid'>[]</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>many1</span> <span class='hs-varid'>p</span>
<a name="line-309"></a>
<a name="line-310"></a><a name="many1"></a><span class='hs-definition'>many1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-311"></a><span class='hs-comment'>-- ^ Parses one or more occurrences of the given parser.</span>
<a name="line-312"></a><span class='hs-definition'>many1</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftM2</span> <span class='hs-layout'>(</span><span class='hs-conop'>:</span><span class='hs-layout'>)</span> <span class='hs-varid'>p</span> <span class='hs-layout'>(</span><span class='hs-varid'>many</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span>
<a name="line-313"></a>
<a name="line-314"></a><a name="skipMany"></a><span class='hs-definition'>skipMany</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>()</span>
<a name="line-315"></a><span class='hs-comment'>-- ^ Like 'many', but discards the result.</span>
<a name="line-316"></a><span class='hs-definition'>skipMany</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>many</span> <span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-317"></a>
<a name="line-318"></a><a name="skipMany1"></a><span class='hs-definition'>skipMany1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-conid'>()</span>
<a name="line-319"></a><span class='hs-comment'>-- ^ Like 'many1', but discards the result.</span>
<a name="line-320"></a><span class='hs-definition'>skipMany1</span> <span class='hs-varid'>p</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>skipMany</span> <span class='hs-varid'>p</span>
<a name="line-321"></a>
<a name="line-322"></a><a name="sepBy"></a><span class='hs-definition'>sepBy</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-323"></a><span class='hs-comment'>-- ^ @sepBy p sep@ parses zero or more occurrences of @p@, separated by @sep@.</span>
<a name="line-324"></a><span class='hs-comment'>--   Returns a list of values returned by @p@.</span>
<a name="line-325"></a><span class='hs-definition'>sepBy</span> <span class='hs-varid'>p</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>sepBy1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>sep</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-conid'>[]</span>
<a name="line-326"></a>
<a name="line-327"></a><a name="sepBy1"></a><span class='hs-definition'>sepBy1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-328"></a><span class='hs-comment'>-- ^ @sepBy1 p sep@ parses one or more occurrences of @p@, separated by @sep@.</span>
<a name="line-329"></a><span class='hs-comment'>--   Returns a list of values returned by @p@.</span>
<a name="line-330"></a><span class='hs-definition'>sepBy1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>liftM2</span> <span class='hs-layout'>(</span><span class='hs-conop'>:</span><span class='hs-layout'>)</span> <span class='hs-varid'>p</span> <span class='hs-layout'>(</span><span class='hs-varid'>many</span> <span class='hs-layout'>(</span><span class='hs-varid'>sep</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>p</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-331"></a>
<a name="line-332"></a><a name="endBy"></a><span class='hs-definition'>endBy</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-333"></a><span class='hs-comment'>-- ^ @endBy p sep@ parses zero or more occurrences of @p@, separated and ended</span>
<a name="line-334"></a><span class='hs-comment'>--   by @sep@.</span>
<a name="line-335"></a><span class='hs-definition'>endBy</span> <span class='hs-varid'>p</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>many</span> <span class='hs-layout'>(</span><span class='hs-keyword'>do</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>p</span> <span class='hs-layout'>;</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>sep</span> <span class='hs-layout'>;</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-336"></a>
<a name="line-337"></a><a name="endBy1"></a><span class='hs-definition'>endBy1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-338"></a><span class='hs-comment'>-- ^ @endBy p sep@ parses one or more occurrences of @p@, separated and ended</span>
<a name="line-339"></a><span class='hs-comment'>--   by @sep@.</span>
<a name="line-340"></a><span class='hs-definition'>endBy1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>sep</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>many1</span> <span class='hs-layout'>(</span><span class='hs-keyword'>do</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>p</span> <span class='hs-layout'>;</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>sep</span> <span class='hs-layout'>;</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-341"></a>
<a name="line-342"></a><a name="chainr"></a><span class='hs-definition'>chainr</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-343"></a><span class='hs-comment'>-- ^ @chainr p op x@ parses zero or more occurrences of @p@, separated by @op@.</span>
<a name="line-344"></a><span class='hs-comment'>--   Returns a value produced by a /right/ associative application of all</span>
<a name="line-345"></a><span class='hs-comment'>--   functions returned by @op@. If there are no occurrences of @p@, @x@ is</span>
<a name="line-346"></a><span class='hs-comment'>--   returned.</span>
<a name="line-347"></a><span class='hs-definition'>chainr</span> <span class='hs-varid'>p</span> <span class='hs-varid'>op</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>chainr1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>op</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-348"></a>
<a name="line-349"></a><a name="chainl"></a><span class='hs-definition'>chainl</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-350"></a><span class='hs-comment'>-- ^ @chainl p op x@ parses zero or more occurrences of @p@, separated by @op@.</span>
<a name="line-351"></a><span class='hs-comment'>--   Returns a value produced by a /left/ associative application of all</span>
<a name="line-352"></a><span class='hs-comment'>--   functions returned by @op@. If there are no occurrences of @p@, @x@ is</span>
<a name="line-353"></a><span class='hs-comment'>--   returned.</span>
<a name="line-354"></a><span class='hs-definition'>chainl</span> <span class='hs-varid'>p</span> <span class='hs-varid'>op</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>chainl1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>op</span> <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-355"></a>
<a name="line-356"></a><a name="chainr1"></a><span class='hs-definition'>chainr1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-357"></a><span class='hs-comment'>-- ^ Like 'chainr', but parses one or more occurrences of @p@.</span>
<a name="line-358"></a><span class='hs-definition'>chainr1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>op</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>scan</span>
<a name="line-359"></a>  <span class='hs-keyword'>where</span> <span class='hs-varid'>scan</span>   <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>rest</span>
<a name="line-360"></a>        <span class='hs-varid'>rest</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>op</span>
<a name="line-361"></a>                    <span class='hs-varid'>y</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>scan</span>
<a name="line-362"></a>                    <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-363"></a>                 <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-364"></a>
<a name="line-365"></a><a name="chainl1"></a><span class='hs-definition'>chainl1</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-366"></a><span class='hs-comment'>-- ^ Like 'chainl', but parses one or more occurrences of @p@.</span>
<a name="line-367"></a><span class='hs-definition'>chainl1</span> <span class='hs-varid'>p</span> <span class='hs-varid'>op</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>p</span> <span class='hs-varop'>&gt;&gt;=</span> <span class='hs-varid'>rest</span>
<a name="line-368"></a>  <span class='hs-keyword'>where</span> <span class='hs-varid'>rest</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <span class='hs-varid'>f</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>op</span>
<a name="line-369"></a>                    <span class='hs-varid'>y</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>p</span>
<a name="line-370"></a>                    <span class='hs-varid'>rest</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>x</span> <span class='hs-varid'>y</span><span class='hs-layout'>)</span>
<a name="line-371"></a>                 <span class='hs-varop'>+++</span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-372"></a>
<a name="line-373"></a><a name="manyTill"></a><span class='hs-definition'>manyTill</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-varid'>end</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span>
<a name="line-374"></a><span class='hs-comment'>-- ^ @manyTill p end@ parses zero or more occurrences of @p@, until @end@</span>
<a name="line-375"></a><span class='hs-comment'>--   succeeds. Returns a list of values returned by @p@.</span>
<a name="line-376"></a><span class='hs-definition'>manyTill</span> <span class='hs-varid'>p</span> <span class='hs-varid'>end</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>scan</span>
<a name="line-377"></a>  <span class='hs-keyword'>where</span> <span class='hs-varid'>scan</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>end</span> <span class='hs-varop'>&gt;&gt;</span> <span class='hs-varid'>return</span> <span class='hs-conid'>[]</span><span class='hs-layout'>)</span> <span class='hs-varop'>&lt;++</span> <span class='hs-layout'>(</span><span class='hs-varid'>liftM2</span> <span class='hs-layout'>(</span><span class='hs-conop'>:</span><span class='hs-layout'>)</span> <span class='hs-varid'>p</span> <span class='hs-varid'>scan</span><span class='hs-layout'>)</span>
<a name="line-378"></a>
<a name="line-379"></a><span class='hs-comment'>-- ---------------------------------------------------------------------------</span>
<a name="line-380"></a><span class='hs-comment'>-- Converting between ReadP and Read</span>
<a name="line-381"></a>
<a name="line-382"></a><a name="readP_to_S"></a><span class='hs-definition'>readP_to_S</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>a</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadS</span> <span class='hs-varid'>a</span>
<a name="line-383"></a><span class='hs-comment'>-- ^ Converts a parser into a Haskell ReadS-style function.</span>
<a name="line-384"></a><span class='hs-comment'>--   This is the main way in which you can \"run\" a 'ReadP' parser:</span>
<a name="line-385"></a><span class='hs-comment'>--   the expanded type is</span>
<a name="line-386"></a><span class='hs-comment'>-- @ readP_to_S :: ReadP a -&gt; String -&gt; [(a,String)] @</span>
<a name="line-387"></a><span class='hs-definition'>readP_to_S</span> <span class='hs-layout'>(</span><span class='hs-conid'>R</span> <span class='hs-varid'>f</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>f</span> <span class='hs-varid'>return</span><span class='hs-layout'>)</span>
<a name="line-388"></a>
<a name="line-389"></a><a name="readS_to_P"></a><span class='hs-definition'>readS_to_P</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ReadS</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>ReadP</span> <span class='hs-varid'>r</span> <span class='hs-varid'>a</span>
<a name="line-390"></a><span class='hs-comment'>-- ^ Converts a Haskell ReadS-style function into a parser.</span>
<a name="line-391"></a><span class='hs-comment'>--   Warning: This introduces local backtracking in the resulting</span>
<a name="line-392"></a><span class='hs-comment'>--   parser, and therefore a possible inefficiency.</span>
<a name="line-393"></a><span class='hs-definition'>readS_to_P</span> <span class='hs-varid'>r</span> <span class='hs-keyglyph'>=</span>
<a name="line-394"></a>  <span class='hs-conid'>R</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>k</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-conid'>Look</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>s</span> <span class='hs-keyglyph'>-&gt;</span> <span class='hs-varid'>final</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>bs''</span> <span class='hs-keyglyph'>|</span> <span class='hs-layout'>(</span><span class='hs-varid'>a</span><span class='hs-layout'>,</span><span class='hs-varid'>s'</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>r</span> <span class='hs-varid'>s</span><span class='hs-layout'>,</span> <span class='hs-varid'>bs''</span> <span class='hs-keyglyph'>&lt;-</span> <span class='hs-varid'>run</span> <span class='hs-layout'>(</span><span class='hs-varid'>k</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-varid'>s'</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
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