[Xmonad] darcs patch: Main.hs: get rid off non-standard pattern guards.

[Donald Bruce Stewart]

joachim.fasting:
> Thu Jun 21 00:04:21 CEST 2007  joachim.fasting at gmail.com
>   * Main.hs: get rid off non-standard pattern guards.
>   Adds another import and looks a bit convoluted, but this is the best I could do.
>   Also, any trailing non-numeric characters (as in --resume 9r) will be ignored,
>   as this code just blindly calls fst if reads returns anything but an empty list
>   (don't know if this is stupid or not).

What's the motivation for this? 

The core outside of StackSet.hs isn't h98 -- and won't be. 

I can understand removing them from StackSet.hs, to allow Catch/YHC to
work on that module (though they're also adding pattern guards to
nhc/yhc iirc), but given the non-StackSet.hs modules aren't H98 anyway,
I don't see what benefit we get from this.

Pattern guards are useful, concise, have been around since 1997, and
feel free to use them.

-- Don