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<h2 class="chapterHead"><span class="titlemark">Chapter&#x00A0;38</span><br /><a
id="x46-31400038"></a><span
class="pcrr7t-">Numeric</span></h2>
<div class="quote">
<div class="verbatim" id="verbatim-462">
module&#x00A0;Numeric&#x00A0;(
&#x00A0;<br />&#x00A0;&#x00A0;&#x00A0;&#x00A0;showSigned,&#x00A0;&#x00A0;showIntAtBase,&#x00A0;&#x00A0;showInt,&#x00A0;&#x00A0;showHex,&#x00A0;&#x00A0;showOct,&#x00A0;&#x00A0;showEFloat,
&#x00A0;<br />&#x00A0;&#x00A0;&#x00A0;&#x00A0;showFFloat,&#x00A0;&#x00A0;showGFloat,&#x00A0;&#x00A0;showFloat,&#x00A0;&#x00A0;floatToDigits,&#x00A0;&#x00A0;readSigned,&#x00A0;&#x00A0;readInt,
&#x00A0;<br />&#x00A0;&#x00A0;&#x00A0;&#x00A0;readDec,&#x00A0;&#x00A0;readOct,&#x00A0;&#x00A0;readHex,&#x00A0;&#x00A0;readFloat,&#x00A0;&#x00A0;lexDigits,&#x00A0;&#x00A0;fromRat
&#x00A0;<br />&#x00A0;&#x00A0;)&#x00A0;where
</div>
<p class="noindent"></div>
<h3 class="sectionHead"><span class="titlemark">38.1 </span> <a
id="x46-31500038.1"></a>Showing </h3>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-608" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-608-1g"><col
id="TBL-608-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-608-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-608-1-1"
class="td11"><span
class="pcrb7t-">showSigned </span></td>
</tr></table> </div> <dd class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"><table id="TBL-609" class="tabulary"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-609-1g"><col
id="TBL-609-1" /><col
id="TBL-609-2" /><col
id="TBL-609-3" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-609-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-609-1-1"
class="td11"> <span
class="pcrb7t-">:: </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-609-1-2"
class="td11"> <span
class="pcrb7t-">Real a </span></td></tr><tr
style="vertical-align:baseline;" id="TBL-609-2-"><td style="white-space:nowrap; text-align:left;" id="TBL-609-2-1"
class="td11"> <span
class="pcrb7t-">=&#x003E; </span></td> <td style="white-space:nowrap; text-align:left;" id="TBL-609-2-2"
class="td11"> <span
class="pcrb7t-">(a -&#x003E; ShowS)</span></td><td style="white-space:wrap; text-align:left;" id="TBL-609-2-3"
class="td11"> a function that can show unsigned values </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-609-3-"><td style="white-space:nowrap; text-align:left;" id="TBL-609-3-1"
class="td11"> <span
class="pcrb7t-">-&#x003E; </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-609-3-2"
class="td11"> <span
class="pcrb7t-">Int </span></td><td style="white-space:wrap; text-align:left;" id="TBL-609-3-3"
class="td11"> the precedence of the enclosing context </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-609-4-"><td style="white-space:nowrap; text-align:left;" id="TBL-609-4-1"
class="td11"> <span
class="pcrb7t-">-&#x003E; </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-609-4-2"
class="td11"> <span
class="pcrb7t-">a </span></td><td style="white-space:wrap; text-align:left;" id="TBL-609-4-3"
class="td11"> the value to show </td></tr><tr
style="vertical-align:baseline;" id="TBL-609-5-"><td style="white-space:nowrap; text-align:left;" id="TBL-609-5-1"
class="td11"> <span
class="pcrb7t-">-&#x003E; </span></td> <td style="white-space:nowrap; text-align:left;" id="TBL-609-5-2"
class="td11"> <span
class="pcrb7t-">ShowS </span></td> <td style="white-space:wrap; text-align:left;" id="TBL-609-5-3"
class="td11"></td>
</tr><tr
style="vertical-align:baseline;" id="TBL-609-6-"><td style="white-space:nowrap; text-align:left;" id="TBL-609-6-1"
class="td11"> </td></tr></table>
</div>
<p class="noindent"> Converts a possibly-negative <span
class="pcrr7t-">Real</span><a
id="dx46-315001"></a> value to a string.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-610" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-610-1g"><col
id="TBL-610-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-610-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-610-1-1"
class="td11"><span
class="pcrb7t-">showIntAtBase</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Integral</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;(Int</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;Char)</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Shows a <span
class="ptmri7t-">non-negative </span><span
class="pcrr7t-">Integral</span><a
id="dx46-315002"></a> number using the base specified by the first argument, and the
character representation specified by the second.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-611" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-611-1g"><col
id="TBL-611-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-611-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-611-1-1"
class="td11"><span
class="pcrb7t-">showInt</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Integral</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Show <span
class="ptmri7t-">non-negative </span><span
class="pcrr7t-">Integral</span><a
id="dx46-315003"></a> numbers in base 10.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-612" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-612-1g"><col
id="TBL-612-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-612-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-612-1-1"
class="td11"><span
class="pcrb7t-">showHex</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Integral</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Show <span
class="ptmri7t-">non-negative </span><span
class="pcrr7t-">Integral</span><a
id="dx46-315004"></a> numbers in base 16.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-613" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-613-1g"><col
id="TBL-613-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-613-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-613-1-1"
class="td11"><span
class="pcrb7t-">showOct</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Integral</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Show <span
class="ptmri7t-">non-negative </span><span
class="pcrr7t-">Integral</span><a
id="dx46-315005"></a> numbers in base 8.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-614" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-614-1g"><col
id="TBL-614-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-614-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-614-1-1"
class="td11"><span
class="pcrb7t-">showEFloat</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFloat</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;Maybe</span><span
class="pcrb7t-">&#x00A0;Int</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Show a signed <span
class="pcrr7t-">RealFloat</span><a
id="dx46-315006"></a> value using scientific (exponential) notation (e.g. <span
class="pcrr7t-">2.45e2</span>, <span
class="pcrr7t-">1.5e-3</span>).
<p class="noindent"> In the call <span
class="pcrr7t-">showEFloat</span><span
class="pcrr7t-">&#x00A0;digs</span><span
class="pcrr7t-">&#x00A0;val</span>, if <span
class="pcrr7t-">digs </span>is <span
class="pcrr7t-">Nothing</span><a
id="dx46-315007"></a>, the value is shown to full precision; if
<span
class="pcrr7t-">digs </span>is <span
class="pcrr7t-">Just</span><span
class="pcrr7t-">&#x00A0;d</span>, then at most <span
class="pcrr7t-">d </span>digits after the decimal point are shown.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-615" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-615-1g"><col
id="TBL-615-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-615-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-615-1-1"
class="td11"><span
class="pcrb7t-">showFFloat</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFloat</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;Maybe</span><span
class="pcrb7t-">&#x00A0;Int</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Show a signed <span
class="pcrr7t-">RealFloat</span><a
id="dx46-315008"></a> value using standard decimal notation (e.g. <span
class="pcrr7t-">245000</span>, <span
class="pcrr7t-">0.0015</span>).
<p class="noindent"> In the call <span
class="pcrr7t-">showFFloat</span><span
class="pcrr7t-">&#x00A0;digs</span><span
class="pcrr7t-">&#x00A0;val</span>, if <span
class="pcrr7t-">digs </span>is <span
class="pcrr7t-">Nothing</span><a
id="dx46-315009"></a>, the value is shown to full precision; if
<span
class="pcrr7t-">digs </span>is <span
class="pcrr7t-">Just</span><span
class="pcrr7t-">&#x00A0;d</span>, then at most <span
class="pcrr7t-">d </span>digits after the decimal point are shown.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-616" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-616-1g"><col
id="TBL-616-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-616-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-616-1-1"
class="td11"><span
class="pcrb7t-">showGFloat</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFloat</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;Maybe</span><span
class="pcrb7t-">&#x00A0;Int</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td>
</tr></table> </div> <dd class="haddockdesc">
Show a signed <span
class="pcrr7t-">RealFloat</span><a
id="dx46-315010"></a> value using standard decimal notation for arguments whose absolute
value lies between <span
class="pcrr7t-">0.1 </span>and <span
class="pcrr7t-">9,999,999</span>, and scientific notation otherwise.
<p class="noindent"> In the call <span
class="pcrr7t-">showGFloat</span><span
class="pcrr7t-">&#x00A0;digs</span><span
class="pcrr7t-">&#x00A0;val</span>, if <span
class="pcrr7t-">digs </span>is <span
class="pcrr7t-">Nothing</span><a
id="dx46-315011"></a>, the value is shown to full precision; if
<span
class="pcrr7t-">digs </span>is <span
class="pcrr7t-">Just</span><span
class="pcrr7t-">&#x00A0;d</span>, then at most <span
class="pcrr7t-">d </span>digits after the decimal point are shown.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-617" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-617-1g"><col
id="TBL-617-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-617-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-617-1-1"
class="td11"><span
class="pcrb7t-">showFloat</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFloat</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ShowS </span></td></tr></table> </div> <dd class="haddockdesc">
Show a signed <span
class="pcrr7t-">RealFloat</span><a
id="dx46-315012"></a> value to full precision using standard decimal notation for arguments
whose absolute value lies between <span
class="pcrr7t-">0.1 </span>and <span
class="pcrr7t-">9,999,999</span>, and scientific notation otherwise.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-618" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-618-1g"><col
id="TBL-618-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-618-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-618-1-1"
class="td11"><span
class="pcrb7t-">floatToDigits</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFloat</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;Integer</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;([Int],</span><span
class="pcrb7t-">&#x00A0;Int) </span></td>
</tr></table> </div> <dd class="haddockdesc">
<span
class="pcrr7t-">floatToDigits</span><a
id="dx46-315013"></a> takes a base and a non-negative <span
class="pcrr7t-">RealFloat</span><a
id="dx46-315014"></a> number, and returns a list of digits
and an exponent. In particular, if <span
class="pcrr7t-">x&#x003E;=0</span>, and
<p class="noindent">
<div class="quote">
<div class="verbatim" id="verbatim-463">
&#x00A0;floatToDigits&#x00A0;base&#x00A0;x&#x00A0;=&#x00A0;([d1,d2,...,dn],&#x00A0;e)
</div>
<p class="noindent"></div>
<p class="noindent"> then
<p class="noindent">
<ol class="enumerate1" >
<li
class="enumerate" id="x46-315016x1">
<div class="quote">
<div class="verbatim" id="verbatim-464">
n&#x00A0;&#x003E;=&#x00A0;1</div>
<p class="noindent"></div>
</li>
<li
class="enumerate" id="x46-315018x2">
<div class="quote">
<div class="verbatim" id="verbatim-465">
x&#x00A0;=&#x00A0;0.d1d2...dn&#x00A0;&#x22C6;&#x00A0;(base&#x22C6;&#x22C6;e)
</div>
<p class="noindent"></div>
</li>
<li
class="enumerate" id="x46-315020x3">
<div class="quote">
<div class="verbatim" id="verbatim-466">
0&#x00A0;&#x003C;=&#x00A0;di&#x00A0;&#x003C;=&#x00A0;base-1</div>
<p class="noindent"></div>
</li></ol>
</dl>
<p class="noindent">
<h3 class="sectionHead"><span class="titlemark">38.2 </span> <a
id="x46-31600038.2"></a>Reading </h3>
<p class="noindent"> <span
class="ptmri7t-">NB: </span><span
class="pcrr7t-">readInt</span><a
id="dx46-316001"></a> is the &#8217;dual&#8217; of <span
class="pcrr7t-">showIntAtBase</span><a
id="dx46-316002"></a>, and <span
class="pcrr7t-">readDec</span><a
id="dx46-316003"></a> is the &#8216;dual&#8217; of <span
class="pcrr7t-">showInt</span><a
id="dx46-316004"></a>. The inconsistent
naming is a historical accident.
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-619" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-619-1g"><col
id="TBL-619-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-619-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-619-1-1"
class="td11"><span
class="pcrb7t-">readSigned</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Real</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;a </span></td>
</tr></table> </div> <dd class="haddockdesc">
Reads a <span
class="ptmri7t-">signed </span><span
class="pcrr7t-">Real</span><a
id="dx46-316005"></a> value, given a reader for an unsigned value.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-620" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-620-1g"><col
id="TBL-620-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-620-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-620-1-1"
class="td11"><span
class="pcrb7t-">readInt </span></td></tr></table> </div> <dd class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"><table id="TBL-621" class="tabulary"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-621-1g"><col
id="TBL-621-1" /><col
id="TBL-621-2" /><col
id="TBL-621-3" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-621-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-621-1-1"
class="td11"> <span
class="pcrb7t-">:: </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-621-1-2"
class="td11"> <span
class="pcrb7t-">Num a </span></td></tr><tr
style="vertical-align:baseline;" id="TBL-621-2-"><td style="white-space:nowrap; text-align:left;" id="TBL-621-2-1"
class="td11"> <span
class="pcrb7t-">=&#x003E; </span></td> <td style="white-space:nowrap; text-align:left;" id="TBL-621-2-2"
class="td11"> <span
class="pcrb7t-">a</span></td><td style="white-space:wrap; text-align:left;" id="TBL-621-2-3"
class="td11"> the base </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-621-3-"><td style="white-space:nowrap; text-align:left;" id="TBL-621-3-1"
class="td11"> <span
class="pcrb7t-">-&#x003E; </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-621-3-2"
class="td11"> <span
class="pcrb7t-">(Char -&#x003E; Bool) </span></td><td style="white-space:wrap; text-align:left;" id="TBL-621-3-3"
class="td11"> a predicate distinguishing valid digits in this base </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-621-4-"><td style="white-space:nowrap; text-align:left;" id="TBL-621-4-1"
class="td11"> <span
class="pcrb7t-">-&#x003E; </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-621-4-2"
class="td11"> <span
class="pcrb7t-">(Char -&#x003E; Int) </span></td><td style="white-space:wrap; text-align:left;" id="TBL-621-4-3"
class="td11"> a function converting a valid digit character to an <span
class="pcrr7t-">Int</span><a
id="dx46-316006"></a> </td>
</tr><tr
style="vertical-align:baseline;" id="TBL-621-5-"><td style="white-space:nowrap; text-align:left;" id="TBL-621-5-1"
class="td11"> <span
class="pcrb7t-">-&#x003E; </span></td><td style="white-space:nowrap; text-align:left;" id="TBL-621-5-2"
class="td11"> <span
class="pcrb7t-">ReadS a </span></td><td style="white-space:wrap; text-align:left;" id="TBL-621-5-3"
class="td11"> </td></tr><tr
style="vertical-align:baseline;" id="TBL-621-6-"><td style="white-space:nowrap; text-align:left;" id="TBL-621-6-1"
class="td11"> </td>
</tr></table></div>
<p class="noindent"> Reads an <span
class="ptmri7t-">unsigned </span><span
class="pcrr7t-">Integral</span><a
id="dx46-316007"></a> value in an arbitrary base.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-622" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-622-1g"><col
id="TBL-622-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-622-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-622-1-1"
class="td11"><span
class="pcrb7t-">readDec</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Num</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;a </span></td></tr></table> </div> <dd class="haddockdesc">
Read an unsigned number in decimal notation.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-623" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-623-1g"><col
id="TBL-623-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-623-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-623-1-1"
class="td11"><span
class="pcrb7t-">readOct</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Num</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;a </span></td></tr></table> </div> <dd class="haddockdesc">
Read an unsigned number in octal notation.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-624" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-624-1g"><col
id="TBL-624-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-624-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-624-1-1"
class="td11"><span
class="pcrb7t-">readHex</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;Num</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;a </span></td></tr></table> </div> <dd class="haddockdesc">
Read an unsigned number in hexadecimal notation. Both upper or lower case letters are allowed.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-625" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-625-1g"><col
id="TBL-625-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-625-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-625-1-1"
class="td11"><span
class="pcrb7t-">readFloat</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFrac</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;a </span></td></tr></table> </div> <dd class="haddockdesc">
Reads an <span
class="ptmri7t-">unsigned </span><span
class="pcrr7t-">RealFrac</span><a
id="dx46-316008"></a> value, expressed in decimal scientific notation.
</dl>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-626" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-626-1g"><col
id="TBL-626-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-626-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-626-1-1"
class="td11"><span
class="pcrb7t-">lexDigits</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;ReadS</span><span
class="pcrb7t-">&#x00A0;String </span></td>
</tr></table> </div> <dd class="haddockdesc">
Reads a non-empty string of decimal digits.
</dl>
<p class="noindent">
<h3 class="sectionHead"><span class="titlemark">38.3 </span> <a
id="x46-31700038.3"></a>Miscellaneous </h3>
<p class="noindent">
<dl> <dt class="haddockdesc">
<!--tex4ht:inline--><div class="tabular"> <table id="TBL-627" class="tabular"
cellspacing="0" cellpadding="0" rules="groups"
><colgroup id="TBL-627-1g"><col
id="TBL-627-1" /></colgroup><tr
style="vertical-align:baseline;" id="TBL-627-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-627-1-1"
class="td11"><span
class="pcrb7t-">fromRat</span><span
class="pcrb7t-">&#x00A0;::</span><span
class="pcrb7t-">&#x00A0;RealFloat</span><span
class="pcrb7t-">&#x00A0;a</span><span
class="pcrb7t-">&#x00A0;=&#x003E;</span><span
class="pcrb7t-">&#x00A0;Rational</span><span
class="pcrb7t-">&#x00A0;-&#x003E;</span><span
class="pcrb7t-">&#x00A0;a </span></td></tr></table> </div> <dd class="haddockdesc">
Converts a <span
class="pcrr7t-">Rational</span><a
id="dx46-317001"></a> value into any type in class <span
class="pcrr7t-">RealFloat</span><a
id="dx46-317002"></a>.
</dl>
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