Case expressions, matching, and "constants"

[Remi Turk]

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On Thu, Jul 17, 2003 at 12:03:19PM +0100, Bayley, Alistair wrote:
> This is what I've turned it into to get it to work. It seems a bit clumsy;
> is there a better way to write this?
>=20
> > test n =3D
> >	case True of
> >		_ | n =3D=3D one -> "one"
> >		  | n =3D=3D two -> "two"
> >		  | otherwise -> "three"

Or you might want to use something like this:
(depending on how much your example resembles the actual code
and the number of variables you want to match)

module Main where

one         =3D 1
two         =3D 2

test n      =3D maybe d id (n `lookup` m)
    where
        m   =3D [(one,    "one")
              ,(two,    "two")
              ]
	d   =3D "three"
--=20
Nobody can be exactly like me. Even I have trouble doing it.

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