[Haskell-cafe] Re: Improved documentation for Bool

David Menendez dave at zednenem.com
Mon Jan 19 21:25:25 EST 2009


On Mon, Jan 19, 2009 at 7:22 PM,  <ajb at spamcop.net> wrote:
>
> And perhaps more to the point, "Boolean" is an adjective, not a noun.
> Therefore, it would be better reserved for a typeclass.

There's also John Meacham's Boolean package.

<http://repetae.net/recent/out/Boolean.html>

> class (Heyting a) => Boolean a where
>    {- the additional axiom that x || not x == top -}

Are there any instances of Boolean that aren't isomorphic to Bool?

(I'm assuming that (||) and (&&) are intended to be idempotent,
commutative, and associative.)

-- 
Dave Menendez <dave at zednenem.com>
<http://www.eyrie.org/~zednenem/>


More information about the Haskell-Cafe mailing list