A bug in hugs
Deling Ren
rende@cs.orst.edu
Fri, 8 Feb 2002 02:07:27 -0800
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Hugs version: Dec 2001. Platform: Windows. Both WinHugs and command line =
hugs have the same bug.
start hugs with -98 option and try the following program:
class Monad m =3D> ExMonad where
raise :: String-> m a
instead of reporting an error, an internal error is raised:
INTERNAL ERROR: inheritFundeps - predicate failed to match it's own =
head!
Regards.
Deling
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<DIV><FONT face=3DArial size=3D2>Hugs version: Dec 2001. Platform: =
Windows. Both=20
WinHugs and command line hugs have the same bug.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>start hugs with -98 option and try the =
following=20
program:</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>class Monad m =3D> ExMonad=20
where<BR> raise :: String-> m a</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>instead of reporting an error, an =
internal error is=20
raised:</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>INTERNAL ERROR: inheritFundeps - =
predicate failed=20
to match it's own head!</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT> </DIV>
<DIV><FONT face=3DArial size=3D2>Regards.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>Deling</FONT></DIV></BODY></HTML>
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