[Haskell-cafe] Very freaky

Dan Piponi dpiponi at gmail.com
Tue Jul 10 16:05:00 EDT 2007

On 7/10/07, Andrew Coppin <andrewcoppin at btinternet.com> wrote:
> But what does, say, "Maybe x -> x" say?

Maybe X is the same as "True or X", where True is the statement that
is always true. Remember that the definition is

data Maybe X = Nothing | Just X

You can read | as 'or', 'Just' as nothing but a wrapper around an X
and Nothing as an axiom.

So Maybe X -> X says that "True or X" implies X. That's a valid proposition.

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