perhaps

Josef Svenningsson josef.svenningsson at gmail.com
Thu Aug 3 08:41:22 EDT 2006


On 8/3/06, John Meacham <john at repetae.net> wrote:
> does anyone else think this would be useful to provide?
>
> > module Data.Perhaps where
> >
> > data Perhaps = No | Maybe | Yes
> >         deriving(Eq,Ord,Show,Read,Enum,Bounded)
> >
> > instance Monoid Perhaps ...
> > ...
>
Reminds me of Donald Knuth's type declaration:

type enum {
  false, true, wow
} bool;

/Josef


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