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<pre><a name="line-1"></a><span class='comment'>-- |</span>
<a name="line-2"></a><span class='comment'>-- utility functions</span>
<a name="line-3"></a><span class='comment'>---- Version : $Id: Util.hs,v 1.3 2006/05/01 18:56:24 hxml Exp $</span>
<a name="line-4"></a>
<a name="line-5"></a><span class='keyword'>module</span> <span class='conid'>Text</span><span class='varop'>.</span><span class='conid'>XML</span><span class='varop'>.</span><span class='conid'>HXT</span><span class='varop'>.</span><span class='conid'>DOM</span><span class='varop'>.</span><span class='conid'>Util</span>
<a name="line-6"></a>    <span class='layout'>(</span> <span class='varid'>stringTrim</span>
<a name="line-7"></a>    <span class='layout'>,</span> <span class='varid'>stringToUpper</span>
<a name="line-8"></a>    <span class='layout'>,</span> <span class='varid'>normalizeNumber</span>
<a name="line-9"></a>    <span class='layout'>,</span> <span class='varid'>normalizeWhitespace</span>
<a name="line-10"></a>    <span class='layout'>,</span> <span class='varid'>normalizeBlanks</span>
<a name="line-11"></a>
<a name="line-12"></a>    <span class='layout'>,</span> <span class='varid'>escapeURI</span>
<a name="line-13"></a>    <span class='layout'>,</span> <span class='varid'>textEscapeXml</span>
<a name="line-14"></a>    <span class='layout'>,</span> <span class='varid'>stringEscapeXml</span>
<a name="line-15"></a>    <span class='layout'>,</span> <span class='varid'>attrEscapeXml</span>
<a name="line-16"></a>
<a name="line-17"></a>    <span class='layout'>,</span> <span class='varid'>stringToInt</span>
<a name="line-18"></a>    <span class='layout'>,</span> <span class='varid'>stringToHexString</span>
<a name="line-19"></a>    <span class='layout'>,</span> <span class='varid'>charToHexString</span>
<a name="line-20"></a>    <span class='layout'>,</span> <span class='varid'>intToHexString</span>
<a name="line-21"></a>    <span class='layout'>,</span> <span class='varid'>hexStringToInt</span>
<a name="line-22"></a>    <span class='layout'>,</span> <span class='varid'>decimalStringToInt</span>
<a name="line-23"></a>
<a name="line-24"></a>    <span class='layout'>,</span> <span class='varid'>doubles</span>
<a name="line-25"></a>    <span class='layout'>,</span> <span class='varid'>singles</span>
<a name="line-26"></a>    <span class='layout'>,</span> <span class='varid'>noDoubles</span>
<a name="line-27"></a>
<a name="line-28"></a>    <span class='layout'>,</span> <span class='varid'>swap</span>
<a name="line-29"></a>    <span class='layout'>,</span> <span class='varid'>partitionEither</span>
<a name="line-30"></a>    <span class='layout'>,</span> <span class='varid'>toMaybe</span>
<a name="line-31"></a>
<a name="line-32"></a>    <span class='layout'>,</span> <span class='varid'>uncurry3</span>
<a name="line-33"></a>    <span class='layout'>,</span> <span class='varid'>uncurry4</span>
<a name="line-34"></a>    <span class='layout'>)</span>
<a name="line-35"></a><span class='keyword'>where</span>
<a name="line-36"></a>
<a name="line-37"></a><span class='keyword'>import</span> <span class='conid'>Data</span><span class='varop'>.</span><span class='conid'>Char</span>
<a name="line-38"></a>
<a name="line-39"></a><span class='comment'>-- ------------------------------------------------------------</span>
<a name="line-40"></a><span class='comment'>-- |</span>
<a name="line-41"></a><span class='comment'>-- remove leading and trailing whitespace with standard Haskell predicate isSpace</span>
<a name="line-42"></a>
<a name="line-43"></a><a name="stringTrim"></a><span class='definition'>stringTrim</span>		<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-44"></a><span class='definition'>stringTrim</span>
<a name="line-45"></a>    <span class='keyglyph'>=</span> <span class='varid'>reverse</span> <span class='varop'>.</span> <span class='varid'>dropWhile</span> <span class='varid'>isSpace</span> <span class='varop'>.</span> <span class='varid'>reverse</span> <span class='varop'>.</span> <span class='varid'>dropWhile</span> <span class='varid'>isSpace</span>
<a name="line-46"></a>
<a name="line-47"></a><span class='comment'>-- |</span>
<a name="line-48"></a><span class='comment'>-- convert string to upercase with standard Haskell toUpper function</span>
<a name="line-49"></a>
<a name="line-50"></a><a name="stringToUpper"></a><span class='definition'>stringToUpper</span>		<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-51"></a><span class='definition'>stringToUpper</span>
<a name="line-52"></a>    <span class='keyglyph'>=</span> <span class='varid'>map</span> <span class='varid'>toUpper</span>
<a name="line-53"></a>
<a name="line-54"></a><span class='comment'>-- | Removes leading \/ trailing whitespaces and leading zeros</span>
<a name="line-55"></a>
<a name="line-56"></a><a name="normalizeNumber"></a><span class='definition'>normalizeNumber</span>		<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-57"></a><span class='definition'>normalizeNumber</span>
<a name="line-58"></a>    <span class='keyglyph'>=</span> <span class='varid'>reverse</span> <span class='varop'>.</span> <span class='varid'>dropWhile</span> <span class='layout'>(</span><span class='varop'>==</span> <span class='chr'>' '</span><span class='layout'>)</span> <span class='varop'>.</span> <span class='varid'>reverse</span> <span class='varop'>.</span> 
<a name="line-59"></a>      <span class='varid'>dropWhile</span> <span class='layout'>(</span><span class='keyglyph'>\</span><span class='varid'>x</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>x</span> <span class='varop'>==</span> <span class='chr'>'0'</span> <span class='varop'>||</span> <span class='varid'>x</span> <span class='varop'>==</span> <span class='chr'>' '</span><span class='layout'>)</span>
<a name="line-60"></a>
<a name="line-61"></a>
<a name="line-62"></a><span class='comment'>-- | Reduce whitespace sequences to a single whitespace</span>
<a name="line-63"></a>
<a name="line-64"></a><a name="normalizeWhitespace"></a><span class='definition'>normalizeWhitespace</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-65"></a><span class='definition'>normalizeWhitespace</span>
<a name="line-66"></a>    <span class='keyglyph'>=</span> <span class='varid'>unwords</span> <span class='varop'>.</span> <span class='varid'>words</span>
<a name="line-67"></a>
<a name="line-68"></a><span class='comment'>-- | replace all whitespace chars by blanks</span>
<a name="line-69"></a>
<a name="line-70"></a><a name="normalizeBlanks"></a><span class='definition'>normalizeBlanks</span>		<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-71"></a><span class='definition'>normalizeBlanks</span>
<a name="line-72"></a>    <span class='keyglyph'>=</span> <span class='varid'>map</span> <span class='layout'>(</span><span class='keyglyph'>\</span> <span class='varid'>x</span> <span class='keyglyph'>-&gt;</span> <span class='keyword'>if</span> <span class='varid'>isSpace</span> <span class='varid'>x</span> <span class='keyword'>then</span> <span class='chr'>' '</span> <span class='keyword'>else</span> <span class='varid'>x</span><span class='layout'>)</span>
<a name="line-73"></a>
<a name="line-74"></a><span class='comment'>-- ------------------------------------------------------------</span>
<a name="line-75"></a>
<a name="line-76"></a><span class='comment'>-- | Escape all disallowed characters in URI </span>
<a name="line-77"></a><span class='comment'>-- references (see &lt;<a href="http://www.w3.org/TR/xlink/#link-locators">http://www.w3.org/TR/xlink/#link-locators</a>&gt;)</span>
<a name="line-78"></a>
<a name="line-79"></a><a name="escapeURI"></a><span class='definition'>escapeURI</span> <span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-80"></a><span class='definition'>escapeURI</span> <span class='varid'>ref</span>
<a name="line-81"></a>    <span class='keyglyph'>=</span> <span class='varid'>concatMap</span> <span class='varid'>replace</span> <span class='varid'>ref</span>
<a name="line-82"></a>      <span class='keyword'>where</span>
<a name="line-83"></a>      <span class='varid'>notAllowed</span>	<span class='keyglyph'>::</span> <span class='conid'>Char</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>Bool</span>
<a name="line-84"></a>      <span class='varid'>notAllowed</span> <span class='varid'>c</span>
<a name="line-85"></a>	  <span class='keyglyph'>=</span> <span class='varid'>c</span> <span class='varop'>&lt;</span> <span class='chr'>'\31'</span>
<a name="line-86"></a>	    <span class='varop'>||</span>
<a name="line-87"></a>	    <span class='varid'>c</span> <span class='varop'>`elem`</span> <span class='keyglyph'>[</span><span class='chr'>'\DEL'</span><span class='layout'>,</span> <span class='chr'>' '</span><span class='layout'>,</span> <span class='chr'>'&lt;'</span><span class='layout'>,</span> <span class='chr'>'&gt;'</span><span class='layout'>,</span> <span class='chr'>'\"'</span><span class='layout'>,</span> <span class='chr'>'{'</span><span class='layout'>,</span> <span class='chr'>'}'</span><span class='layout'>,</span> <span class='chr'>'|'</span><span class='layout'>,</span> <span class='chr'>'\\'</span><span class='layout'>,</span> <span class='chr'>'^'</span><span class='layout'>,</span> <span class='chr'>'`'</span> <span class='keyglyph'>]</span>
<a name="line-88"></a>
<a name="line-89"></a>      <span class='varid'>replace</span> <span class='keyglyph'>::</span> <span class='conid'>Char</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-90"></a>      <span class='varid'>replace</span> <span class='varid'>c</span>
<a name="line-91"></a>	  <span class='keyglyph'>|</span> <span class='varid'>notAllowed</span> <span class='varid'>c</span>
<a name="line-92"></a>	      <span class='keyglyph'>=</span> <span class='chr'>'%'</span> <span class='conop'>:</span> <span class='varid'>charToHexString</span> <span class='varid'>c</span>
<a name="line-93"></a>	  <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>
<a name="line-94"></a>	      <span class='keyglyph'>=</span> <span class='keyglyph'>[</span><span class='varid'>c</span><span class='keyglyph'>]</span>
<a name="line-95"></a>
<a name="line-96"></a><span class='comment'>-- ------------------------------------------------------------</span>
<a name="line-97"></a>
<a name="line-98"></a><a name="escapeXml"></a><span class='definition'>escapeXml</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-99"></a><span class='definition'>escapeXml</span> <span class='varid'>escSet</span>
<a name="line-100"></a>    <span class='keyglyph'>=</span> <span class='varid'>concatMap</span> <span class='varid'>esc</span>
<a name="line-101"></a>      <span class='keyword'>where</span>
<a name="line-102"></a>      <span class='varid'>esc</span> <span class='varid'>c</span>
<a name="line-103"></a>	  <span class='keyglyph'>|</span> <span class='varid'>c</span> <span class='varop'>`elem`</span> <span class='varid'>escSet</span>
<a name="line-104"></a>	      <span class='keyglyph'>=</span> <span class='str'>"&amp;#"</span> <span class='varop'>++</span> <span class='varid'>show</span> <span class='layout'>(</span><span class='varid'>fromEnum</span> <span class='varid'>c</span><span class='layout'>)</span> <span class='varop'>++</span> <span class='str'>";"</span>
<a name="line-105"></a>	  <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>
<a name="line-106"></a>	      <span class='keyglyph'>=</span> <span class='keyglyph'>[</span><span class='varid'>c</span><span class='keyglyph'>]</span>
<a name="line-107"></a>
<a name="line-108"></a><span class='comment'>-- |</span>
<a name="line-109"></a><span class='comment'>-- escape XML chars &amp;lt;, &amp;gt;, &amp;quot;,  and ampercent by transforming them into character references</span>
<a name="line-110"></a><span class='comment'>--</span>
<a name="line-111"></a><span class='comment'>-- see also : 'attrEscapeXml'</span>
<a name="line-112"></a>
<a name="line-113"></a><a name="stringEscapeXml"></a><span class='definition'>stringEscapeXml</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-114"></a><span class='definition'>stringEscapeXml</span>	<span class='keyglyph'>=</span> <span class='varid'>escapeXml</span> <span class='str'>"&lt;&gt;\"\'&amp;"</span>
<a name="line-115"></a>
<a name="line-116"></a><span class='comment'>-- |</span>
<a name="line-117"></a><span class='comment'>-- escape XML chars &amp;lt;  and ampercent by transforming them into character references, used for escaping text nodes</span>
<a name="line-118"></a><span class='comment'>--</span>
<a name="line-119"></a><span class='comment'>-- see also : 'attrEscapeXml'</span>
<a name="line-120"></a>
<a name="line-121"></a><a name="textEscapeXml"></a><span class='definition'>textEscapeXml</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-122"></a><span class='definition'>textEscapeXml</span>	<span class='keyglyph'>=</span> <span class='varid'>escapeXml</span> <span class='str'>"&lt;&amp;"</span>
<a name="line-123"></a>
<a name="line-124"></a><span class='comment'>-- |</span>
<a name="line-125"></a><span class='comment'>-- escape XML chars in attribute values, same as stringEscapeXml, but none blank whitespace</span>
<a name="line-126"></a><span class='comment'>-- is also escaped</span>
<a name="line-127"></a><span class='comment'>--</span>
<a name="line-128"></a><span class='comment'>-- see also : 'stringEscapeXml'</span>
<a name="line-129"></a>
<a name="line-130"></a><a name="attrEscapeXml"></a><span class='definition'>attrEscapeXml</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-131"></a><span class='definition'>attrEscapeXml</span>	<span class='keyglyph'>=</span> <span class='varid'>escapeXml</span> <span class='str'>"&lt;&gt;\"\'&amp;\n\r\t"</span>
<a name="line-132"></a>
<a name="line-133"></a><a name="stringToInt"></a><span class='definition'>stringToInt</span>	<span class='keyglyph'>::</span> <span class='conid'>Int</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>Int</span>
<a name="line-134"></a><span class='definition'>stringToInt</span> <span class='varid'>base</span> <span class='varid'>digits</span>
<a name="line-135"></a>    <span class='keyglyph'>=</span> <span class='varid'>sign</span> <span class='varop'>*</span> <span class='layout'>(</span><span class='varid'>foldl</span> <span class='varid'>acc</span> <span class='num'>0</span> <span class='varop'>$</span> <span class='varid'>concatMap</span> <span class='varid'>digToInt</span> <span class='varid'>digits1</span><span class='layout'>)</span>
<a name="line-136"></a>      <span class='keyword'>where</span>
<a name="line-137"></a>      <span class='varid'>splitSign</span> <span class='layout'>(</span><span class='chr'>'-'</span> <span class='conop'>:</span> <span class='varid'>ds</span><span class='layout'>)</span> <span class='keyglyph'>=</span> <span class='layout'>(</span><span class='layout'>(</span><span class='comment'>-</span><span class='num'>1</span><span class='layout'>)</span><span class='layout'>,</span> <span class='varid'>ds</span><span class='layout'>)</span>
<a name="line-138"></a>      <span class='varid'>splitSign</span> <span class='layout'>(</span><span class='chr'>'+'</span> <span class='conop'>:</span> <span class='varid'>ds</span><span class='layout'>)</span> <span class='keyglyph'>=</span> <span class='layout'>(</span> <span class='num'>1</span>  <span class='layout'>,</span> <span class='varid'>ds</span><span class='layout'>)</span>
<a name="line-139"></a>      <span class='varid'>splitSign</span> <span class='varid'>ds</span>         <span class='keyglyph'>=</span> <span class='layout'>(</span> <span class='num'>1</span>  <span class='layout'>,</span> <span class='varid'>ds</span><span class='layout'>)</span>
<a name="line-140"></a>      <span class='layout'>(</span><span class='varid'>sign</span><span class='layout'>,</span> <span class='varid'>digits1</span><span class='layout'>)</span>      <span class='keyglyph'>=</span> <span class='varid'>splitSign</span> <span class='varid'>digits</span>
<a name="line-141"></a>      <span class='varid'>digToInt</span> <span class='varid'>c</span>
<a name="line-142"></a>	  <span class='keyglyph'>|</span> <span class='varid'>c</span> <span class='varop'>&gt;=</span> <span class='chr'>'0'</span> <span class='varop'>&amp;&amp;</span> <span class='varid'>c</span> <span class='varop'>&lt;=</span> <span class='chr'>'9'</span>
<a name="line-143"></a>	      <span class='keyglyph'>=</span> <span class='keyglyph'>[</span><span class='varid'>ord</span> <span class='varid'>c</span> <span class='comment'>-</span> <span class='varid'>ord</span> <span class='chr'>'0'</span><span class='keyglyph'>]</span>
<a name="line-144"></a>	  <span class='keyglyph'>|</span> <span class='varid'>c</span> <span class='varop'>&gt;=</span> <span class='chr'>'A'</span> <span class='varop'>&amp;&amp;</span> <span class='varid'>c</span> <span class='varop'>&lt;=</span> <span class='chr'>'Z'</span>
<a name="line-145"></a>	      <span class='keyglyph'>=</span>  <span class='keyglyph'>[</span><span class='varid'>ord</span> <span class='varid'>c</span> <span class='comment'>-</span> <span class='varid'>ord</span> <span class='chr'>'A'</span> <span class='varop'>+</span> <span class='num'>10</span><span class='keyglyph'>]</span>
<a name="line-146"></a>	  <span class='keyglyph'>|</span> <span class='varid'>c</span> <span class='varop'>&gt;=</span> <span class='chr'>'a'</span> <span class='varop'>&amp;&amp;</span> <span class='varid'>c</span> <span class='varop'>&lt;=</span> <span class='chr'>'z'</span>
<a name="line-147"></a>	      <span class='keyglyph'>=</span>  <span class='keyglyph'>[</span><span class='varid'>ord</span> <span class='varid'>c</span> <span class='comment'>-</span> <span class='varid'>ord</span> <span class='chr'>'a'</span> <span class='varop'>+</span> <span class='num'>10</span><span class='keyglyph'>]</span>
<a name="line-148"></a>	  <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>
<a name="line-149"></a>	      <span class='keyglyph'>=</span> <span class='conid'>[]</span>
<a name="line-150"></a>      <span class='varid'>acc</span> <span class='varid'>i1</span> <span class='varid'>i0</span>
<a name="line-151"></a>	  <span class='keyglyph'>=</span> <span class='varid'>i1</span> <span class='varop'>*</span> <span class='varid'>base</span> <span class='varop'>+</span> <span class='varid'>i0</span>
<a name="line-152"></a>
<a name="line-153"></a>
<a name="line-154"></a><span class='comment'>-- |</span>
<a name="line-155"></a><span class='comment'>-- convert a string of hexadecimal digits into an Int</span>
<a name="line-156"></a>
<a name="line-157"></a><a name="hexStringToInt"></a><span class='definition'>hexStringToInt</span>		<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>Int</span>
<a name="line-158"></a><span class='definition'>hexStringToInt</span>		<span class='keyglyph'>=</span> <span class='varid'>stringToInt</span> <span class='num'>16</span>
<a name="line-159"></a>
<a name="line-160"></a><span class='comment'>-- |</span>
<a name="line-161"></a><span class='comment'>-- convert a string of digits into an Int</span>
<a name="line-162"></a>
<a name="line-163"></a><a name="decimalStringToInt"></a><span class='definition'>decimalStringToInt</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>Int</span>
<a name="line-164"></a><span class='definition'>decimalStringToInt</span>	<span class='keyglyph'>=</span> <span class='varid'>stringToInt</span> <span class='num'>10</span>
<a name="line-165"></a>
<a name="line-166"></a><span class='comment'>-- |</span>
<a name="line-167"></a><span class='comment'>-- convert a string into a hexadecimal string applying charToHexString</span>
<a name="line-168"></a><span class='comment'>--</span>
<a name="line-169"></a><span class='comment'>-- see also : 'charToHexString'</span>
<a name="line-170"></a>
<a name="line-171"></a><a name="stringToHexString"></a><span class='definition'>stringToHexString</span>	<span class='keyglyph'>::</span> <span class='conid'>String</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-172"></a><span class='definition'>stringToHexString</span>	<span class='keyglyph'>=</span> <span class='varid'>concatMap</span> <span class='varid'>charToHexString</span>
<a name="line-173"></a>
<a name="line-174"></a><span class='comment'>-- |</span>
<a name="line-175"></a><span class='comment'>-- convert a char (byte) into a 2-digit hexadecimal string</span>
<a name="line-176"></a><span class='comment'>--</span>
<a name="line-177"></a><span class='comment'>-- see also : 'stringToHexString', 'intToHexString'</span>
<a name="line-178"></a>
<a name="line-179"></a><a name="charToHexString"></a><span class='definition'>charToHexString</span>		<span class='keyglyph'>::</span> <span class='conid'>Char</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-180"></a><span class='definition'>charToHexString</span> <span class='varid'>c</span>
<a name="line-181"></a>    <span class='keyglyph'>=</span> <span class='keyglyph'>[</span> <span class='varid'>fourBitsToChar</span> <span class='layout'>(</span><span class='varid'>c'</span> <span class='varop'>`div`</span> <span class='num'>16</span><span class='layout'>)</span>
<a name="line-182"></a>      <span class='layout'>,</span> <span class='varid'>fourBitsToChar</span> <span class='layout'>(</span><span class='varid'>c'</span> <span class='varop'>`mod`</span> <span class='num'>16</span><span class='layout'>)</span>
<a name="line-183"></a>      <span class='keyglyph'>]</span>
<a name="line-184"></a>    <span class='keyword'>where</span>
<a name="line-185"></a>    <span class='varid'>c'</span> <span class='keyglyph'>=</span> <span class='varid'>fromEnum</span> <span class='varid'>c</span>
<a name="line-186"></a>
<a name="line-187"></a><span class='comment'>-- |</span>
<a name="line-188"></a><span class='comment'>-- convert a none negative Int into a hexadecimal string</span>
<a name="line-189"></a><span class='comment'>--</span>
<a name="line-190"></a><span class='comment'>-- see also : 'charToHexString'</span>
<a name="line-191"></a>
<a name="line-192"></a><a name="intToHexString"></a><span class='definition'>intToHexString</span>		<span class='keyglyph'>::</span> <span class='conid'>Int</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>String</span>
<a name="line-193"></a><span class='definition'>intToHexString</span> <span class='varid'>i</span>
<a name="line-194"></a>    <span class='keyglyph'>|</span> <span class='varid'>i</span> <span class='varop'>==</span> <span class='num'>0</span>
<a name="line-195"></a>	<span class='keyglyph'>=</span> <span class='str'>"0"</span>
<a name="line-196"></a>    <span class='keyglyph'>|</span> <span class='varid'>i</span> <span class='varop'>&gt;</span> <span class='num'>0</span>
<a name="line-197"></a>	<span class='keyglyph'>=</span> <span class='varid'>intToStr</span> <span class='varid'>i</span>
<a name="line-198"></a>    <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>
<a name="line-199"></a>	<span class='keyglyph'>=</span> <span class='varid'>error</span> <span class='layout'>(</span><span class='str'>"intToHexString: negative argument "</span> <span class='varop'>++</span> <span class='varid'>show</span> <span class='varid'>i</span><span class='layout'>)</span>
<a name="line-200"></a>    <span class='keyword'>where</span>
<a name="line-201"></a>    <span class='varid'>intToStr</span> <span class='num'>0</span>	<span class='keyglyph'>=</span> <span class='str'>""</span>
<a name="line-202"></a>    <span class='varid'>intToStr</span> <span class='varid'>i'</span>	<span class='keyglyph'>=</span> <span class='varid'>intToStr</span> <span class='layout'>(</span><span class='varid'>i'</span> <span class='varop'>`div`</span> <span class='num'>16</span><span class='layout'>)</span> <span class='varop'>++</span> <span class='keyglyph'>[</span><span class='varid'>fourBitsToChar</span> <span class='layout'>(</span><span class='varid'>i'</span> <span class='varop'>`mod`</span> <span class='num'>16</span><span class='layout'>)</span><span class='keyglyph'>]</span>
<a name="line-203"></a>
<a name="line-204"></a><a name="fourBitsToChar"></a><span class='definition'>fourBitsToChar</span>		<span class='keyglyph'>::</span> <span class='conid'>Int</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>Char</span>
<a name="line-205"></a><span class='definition'>fourBitsToChar</span> <span class='varid'>i</span>	<span class='keyglyph'>=</span> <span class='str'>"0123456789ABCDEF"</span> <span class='varop'>!!</span> <span class='varid'>i</span>
<a name="line-206"></a>
<a name="line-207"></a><span class='comment'>-- ------------------------------------------------------------</span>
<a name="line-208"></a>
<a name="line-209"></a><span class='comment'>-- |</span>
<a name="line-210"></a><span class='comment'>-- take all elements of a list which occur more than once. The result does not contain doubles.</span>
<a name="line-211"></a><span class='comment'>-- (doubles . doubles == doubles)</span>
<a name="line-212"></a>
<a name="line-213"></a><a name="doubles"></a><span class='definition'>doubles</span>	<span class='keyglyph'>::</span> <span class='conid'>Eq</span> <span class='varid'>a</span> <span class='keyglyph'>=&gt;</span> <span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span> <span class='keyglyph'>-&gt;</span> <span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span>
<a name="line-214"></a><span class='definition'>doubles</span>
<a name="line-215"></a>    <span class='keyglyph'>=</span> <span class='varid'>doubles'</span> <span class='conid'>[]</span>
<a name="line-216"></a>      <span class='keyword'>where</span>
<a name="line-217"></a>      <span class='varid'>doubles'</span> <span class='varid'>acc</span> <span class='conid'>[]</span>
<a name="line-218"></a>	  <span class='keyglyph'>=</span> <span class='varid'>acc</span>
<a name="line-219"></a>      <span class='varid'>doubles'</span> <span class='varid'>acc</span> <span class='layout'>(</span><span class='varid'>e</span> <span class='conop'>:</span> <span class='varid'>s</span><span class='layout'>)</span>
<a name="line-220"></a>	  <span class='keyglyph'>|</span> <span class='varid'>e</span> <span class='varop'>`elem`</span> <span class='varid'>s</span>
<a name="line-221"></a>	    <span class='varop'>&amp;&amp;</span>
<a name="line-222"></a>	    <span class='varid'>e</span> <span class='varop'>`notElem`</span> <span class='varid'>acc</span>
<a name="line-223"></a>	      <span class='keyglyph'>=</span> <span class='varid'>doubles'</span> <span class='layout'>(</span><span class='varid'>e</span><span class='conop'>:</span><span class='varid'>acc</span><span class='layout'>)</span> <span class='varid'>s</span>
<a name="line-224"></a>	  <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>
<a name="line-225"></a>	      <span class='keyglyph'>=</span> <span class='varid'>doubles'</span> <span class='varid'>acc</span> <span class='varid'>s</span>
<a name="line-226"></a>
<a name="line-227"></a><span class='comment'>-- |</span>
<a name="line-228"></a><span class='comment'>-- drop all elements from a list which occur more than once.</span>
<a name="line-229"></a>
<a name="line-230"></a><a name="singles"></a><span class='definition'>singles</span>	<span class='keyglyph'>::</span> <span class='conid'>Eq</span> <span class='varid'>a</span> <span class='keyglyph'>=&gt;</span> <span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span> <span class='keyglyph'>-&gt;</span> <span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span>
<a name="line-231"></a><span class='definition'>singles</span>
<a name="line-232"></a>    <span class='keyglyph'>=</span> <span class='varid'>singles'</span> <span class='conid'>[]</span>
<a name="line-233"></a>      <span class='keyword'>where</span>
<a name="line-234"></a>      <span class='varid'>singles'</span> <span class='varid'>acc</span> <span class='conid'>[]</span>
<a name="line-235"></a>	  <span class='keyglyph'>=</span> <span class='varid'>acc</span>
<a name="line-236"></a>      <span class='varid'>singles'</span> <span class='varid'>acc</span> <span class='layout'>(</span><span class='varid'>e</span> <span class='conop'>:</span> <span class='varid'>s</span><span class='layout'>)</span>
<a name="line-237"></a>	  <span class='keyglyph'>|</span> <span class='varid'>e</span> <span class='varop'>`elem`</span> <span class='varid'>s</span>
<a name="line-238"></a>	    <span class='varop'>||</span>
<a name="line-239"></a>	    <span class='varid'>e</span> <span class='varop'>`elem`</span> <span class='varid'>acc</span>
<a name="line-240"></a>	      <span class='keyglyph'>=</span> <span class='varid'>singles'</span> <span class='varid'>acc</span> <span class='varid'>s</span>
<a name="line-241"></a>	  <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>
<a name="line-242"></a>	      <span class='keyglyph'>=</span> <span class='varid'>singles'</span> <span class='layout'>(</span><span class='varid'>e</span> <span class='conop'>:</span> <span class='varid'>acc</span><span class='layout'>)</span> <span class='varid'>s</span>
<a name="line-243"></a>
<a name="line-244"></a><span class='comment'>-- |</span>
<a name="line-245"></a><span class='comment'>-- remove duplicates from list</span>
<a name="line-246"></a>
<a name="line-247"></a><a name="noDoubles"></a><span class='definition'>noDoubles</span> <span class='keyglyph'>::</span> <span class='conid'>Eq</span> <span class='varid'>a</span> <span class='keyglyph'>=&gt;</span> <span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span> <span class='keyglyph'>-&gt;</span> <span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span>
<a name="line-248"></a><span class='definition'>noDoubles</span> <span class='conid'>[]</span>
<a name="line-249"></a>    <span class='keyglyph'>=</span> <span class='conid'>[]</span>
<a name="line-250"></a><span class='definition'>noDoubles</span> <span class='layout'>(</span><span class='varid'>e</span> <span class='conop'>:</span> <span class='varid'>s</span><span class='layout'>)</span>
<a name="line-251"></a>    <span class='keyglyph'>|</span> <span class='varid'>e</span> <span class='varop'>`elem`</span> <span class='varid'>s</span> <span class='keyglyph'>=</span> <span class='varid'>noDoubles</span> <span class='varid'>s</span>
<a name="line-252"></a>    <span class='keyglyph'>|</span> <span class='varid'>otherwise</span>  <span class='keyglyph'>=</span> <span class='varid'>e</span> <span class='conop'>:</span> <span class='varid'>noDoubles</span> <span class='varid'>s</span>
<a name="line-253"></a>
<a name="line-254"></a><span class='comment'>-- ------------------------------------------------------------</span>
<a name="line-255"></a>
<a name="line-256"></a><a name="swap"></a><span class='definition'>swap</span> <span class='keyglyph'>::</span> <span class='layout'>(</span><span class='varid'>a</span><span class='layout'>,</span><span class='varid'>b</span><span class='layout'>)</span> <span class='keyglyph'>-&gt;</span> <span class='layout'>(</span><span class='varid'>b</span><span class='layout'>,</span><span class='varid'>a</span><span class='layout'>)</span>
<a name="line-257"></a><span class='definition'>swap</span> <span class='layout'>(</span><span class='varid'>x</span><span class='layout'>,</span><span class='varid'>y</span><span class='layout'>)</span> <span class='keyglyph'>=</span> <span class='layout'>(</span><span class='varid'>y</span><span class='layout'>,</span><span class='varid'>x</span><span class='layout'>)</span>
<a name="line-258"></a>
<a name="line-259"></a><a name="partitionEither"></a><span class='definition'>partitionEither</span> <span class='keyglyph'>::</span> <span class='keyglyph'>[</span><span class='conid'>Either</span> <span class='varid'>a</span> <span class='varid'>b</span><span class='keyglyph'>]</span> <span class='keyglyph'>-&gt;</span> <span class='layout'>(</span><span class='keyglyph'>[</span><span class='varid'>a</span><span class='keyglyph'>]</span><span class='layout'>,</span> <span class='keyglyph'>[</span><span class='varid'>b</span><span class='keyglyph'>]</span><span class='layout'>)</span>
<a name="line-260"></a><span class='definition'>partitionEither</span> <span class='keyglyph'>=</span>
<a name="line-261"></a>   <span class='varid'>foldr</span> <span class='layout'>(</span><span class='keyglyph'>\</span><span class='varid'>x</span> <span class='keyglyph'>~</span><span class='layout'>(</span><span class='varid'>ls</span><span class='layout'>,</span><span class='varid'>rs</span><span class='layout'>)</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>either</span> <span class='layout'>(</span><span class='keyglyph'>\</span><span class='varid'>l</span> <span class='keyglyph'>-&gt;</span> <span class='layout'>(</span><span class='varid'>l</span><span class='conop'>:</span><span class='varid'>ls</span><span class='layout'>,</span><span class='varid'>rs</span><span class='layout'>)</span><span class='layout'>)</span> <span class='layout'>(</span><span class='keyglyph'>\</span><span class='varid'>r</span> <span class='keyglyph'>-&gt;</span> <span class='layout'>(</span><span class='varid'>ls</span><span class='layout'>,</span><span class='varid'>r</span><span class='conop'>:</span><span class='varid'>rs</span><span class='layout'>)</span><span class='layout'>)</span> <span class='varid'>x</span><span class='layout'>)</span> <span class='layout'>(</span><span class='conid'>[]</span><span class='layout'>,</span><span class='conid'>[]</span><span class='layout'>)</span>
<a name="line-262"></a>
<a name="line-263"></a><a name="toMaybe"></a><span class='definition'>toMaybe</span> <span class='keyglyph'>::</span> <span class='conid'>Bool</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>a</span> <span class='keyglyph'>-&gt;</span> <span class='conid'>Maybe</span> <span class='varid'>a</span>
<a name="line-264"></a><span class='definition'>toMaybe</span> <span class='conid'>False</span> <span class='keyword'>_</span> <span class='keyglyph'>=</span> <span class='conid'>Nothing</span>
<a name="line-265"></a><span class='definition'>toMaybe</span> <span class='conid'>True</span>  <span class='varid'>x</span> <span class='keyglyph'>=</span> <span class='conid'>Just</span> <span class='varid'>x</span>
<a name="line-266"></a>
<a name="line-267"></a><span class='comment'>-- ------------------------------------------------------------</span>
<a name="line-268"></a>
<a name="line-269"></a><span class='comment'>-- | mothers little helpers for to much curry</span>
<a name="line-270"></a>
<a name="line-271"></a><a name="uncurry3"></a><span class='definition'>uncurry3</span>			<span class='keyglyph'>::</span> <span class='layout'>(</span><span class='varid'>a</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>b</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>c</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>d</span><span class='layout'>)</span> <span class='keyglyph'>-&gt;</span> <span class='layout'>(</span><span class='varid'>a</span><span class='layout'>,</span> <span class='varid'>b</span><span class='layout'>,</span> <span class='varid'>c</span><span class='layout'>)</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>d</span>
<a name="line-272"></a><span class='definition'>uncurry3</span> <span class='varid'>f</span> <span class='keyglyph'>~</span><span class='layout'>(</span><span class='varid'>a</span><span class='layout'>,</span> <span class='varid'>b</span><span class='layout'>,</span> <span class='varid'>c</span><span class='layout'>)</span>		<span class='keyglyph'>=</span> <span class='varid'>f</span> <span class='varid'>a</span> <span class='varid'>b</span> <span class='varid'>c</span>
<a name="line-273"></a>
<a name="line-274"></a><a name="uncurry4"></a><span class='definition'>uncurry4</span>			<span class='keyglyph'>::</span> <span class='layout'>(</span><span class='varid'>a</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>b</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>c</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>d</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>e</span><span class='layout'>)</span> <span class='keyglyph'>-&gt;</span> <span class='layout'>(</span><span class='varid'>a</span><span class='layout'>,</span> <span class='varid'>b</span><span class='layout'>,</span> <span class='varid'>c</span><span class='layout'>,</span> <span class='varid'>d</span><span class='layout'>)</span> <span class='keyglyph'>-&gt;</span> <span class='varid'>e</span>
<a name="line-275"></a><span class='definition'>uncurry4</span> <span class='varid'>f</span> <span class='keyglyph'>~</span><span class='layout'>(</span><span class='varid'>a</span><span class='layout'>,</span> <span class='varid'>b</span><span class='layout'>,</span> <span class='varid'>c</span><span class='layout'>,</span> <span class='varid'>d</span><span class='layout'>)</span>	<span class='keyglyph'>=</span> <span class='varid'>f</span> <span class='varid'>a</span> <span class='varid'>b</span> <span class='varid'>c</span> <span class='varid'>d</span>
<a name="line-276"></a>
<a name="line-277"></a><span class='comment'>-- ------------------------------------------------------------</span>
</pre></body>
</html>