[Haskell-cafe] Floating instance and pi

Deniz Dogan deniz.a.m.dogan at gmail.com
Fri May 29 12:01:32 EDT 2009

2009/5/29 Paul Keir <pkeir at dcs.gla.ac.uk>:
> Hi,
> I'd like to make my ADT an instance of the Floating class,
> but I'm not sure what to put for pi, and GHC gives a warning
> without it:
> Warning: No explicit method nor default method for `GHC.Float.pi'
> I tried setting it to undefined, but that gives an error:
> `pi' is not a (visible) method of class `Floating'
> Any idea?
> Paul

Are you sure that your ADT fits into the Floating class in the first
place?  I reckon if it did, defining "pi" for it wouldn't be a
problem.  Could you show us the code you have?

Deniz Dogan

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