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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Yes sorry….but this still fails with….<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>“`numberType1' is a rigid type
variable bound by”<o:p></o:p></span></font></p>
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10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal style='margin-left:36.0pt'><b><font size=2 face=Tahoma><span
lang=EN-US style='font-size:10.0pt;font-family:Tahoma;font-weight:bold'>From:</span></font></b><font
size=2 face=Tahoma><span lang=EN-US style='font-size:10.0pt;font-family:Tahoma'>
Brent Yorgey [mailto:byorgey@gmail.com] <br>
<b><span style='font-weight:bold'>Sent:</span></b> 21 December 2007 17:29<br>
<b><span style='font-weight:bold'>To:</span></b> Nicholls, Mark<br>
<b><span style='font-weight:bold'>Cc:</span></b> Jules Bean;
haskell-cafe@haskell.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> Re: [Haskell-cafe] nice
simple problem for someone struggling....</span></font><span lang=EN-US><o:p></o:p></span></p>
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<p class=MsoNormal style='margin-left:36.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
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face="Times New Roman"><span style='font-size:12.0pt'><o:p> </o:p></span></font></p>
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12.0pt;margin-left:36.0pt'><font size=3 face="Times New Roman"><span
style='font-size:12.0pt'><br>
"class ShapeInterface shape where<br>
area :: shape->Int"<o:p></o:p></span></font></p>
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<p class=MsoNormal style='margin-left:36.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'>now looks dubious....I
want it to be something like<br>
<br>
"class ShapeInterface shape where<br>
area :: Num numberType => shape->Int" ?<o:p></o:p></span></font></p>
</blockquote>
<p class=MsoNormal style='margin-left:36.0pt'><font size=3
face="Times New Roman"><span style='font-size:12.0pt'><br>
Rather, I think you probably want<br>
<br>
class ShapeInterface shape where<br>
area :: Num numberType => shape -> numberType<br>
<br>
-Brent<o:p></o:p></span></font></p>
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