Laws and partial values (was: [Haskell-cafe] mapM_ -> Monoid.Monad.map)

[Luke Palmer]

On Sun, Jan 25, 2009 at 8:00 AM, Jonathan Cast <jonathanccast at fastmail.fm>wrote:

> On Sat, 2009-01-24 at 03:08 -0700, Luke Palmer wrote:
> > On Sat, Jan 24, 2009 at 2:40 AM, Ryan Ingram <ryani.spam at gmail.com>
> > wrote:
> >         But _|_ is not ().
> >
> > Correction: _|_ is not always ().
>
> For example: in Haskell.
>
> Prelude> () `seq` True
> True
> Prelude> (undefined `asTypeOf` ()) `seq` True
> *** Exception: Prelude.undefined


Gee, I'm sure glad that I wrote that detailed analysis of what I meant.
It's nice to see people responding to arguments rather than opinions for
once.

Luke
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