this is the same as the function 'fromMaybe' in Data.Maybe.  the 'maybe' 
function in that library is also incredibly useful.

On Wed, 12 Nov 2003, Andrew Pimlott wrote:

> On Wed, Nov 12, 2003 at 02:54:32PM +0000, Graham Klyne wrote:
> > I just spotted a possible idiom for something that seems to pop up from 
> > time to time:
> > 
> >    foldr const
> > 
> > But I can't help feeling that this code is perversely obscure.
> 
> Clever.  I usually end up with something like
> 
>     listToMaybe list `orMaybe` default
> 
>     orMaybe (Just x) _  = x
>     orMaybe Nothing  y  = y
> 
> Andrew
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-- 
 Hal Daume III                                   | [EMAIL PROTECTED]
 "Arrest this man, he talks in maths."           | www.isi.edu/~hdaume

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