Easy syntax question

Mark Carroll [email protected]
Wed, 29 Aug 2001 12:16:18 -0400 (EDT)


On 27 Aug 2001, Mike Gunter wrote:

(snip)
> Or, if you need several cases, you can use something like:
> 
> 
> > funcGuard n | n `elem` [2,5,9]   = 5
> >             | n `elem` [4,18]    = 1
> >             | otherwise          = 7 
>   
> or, if you want an expression:
> 
> > caseGuard n     = case undefined of
> >                    _ | n `elem` [2,5,9]   -> 5
> >                      | n `elem` [4,18]    -> 1
> >                      | otherwise          -> 7

Thanks - that's very helpful! (-: I hadn't thought of using 'elem'. Most
of the cases are going to be ones like "if x = 5 or x = 7" instead of "if
x = 6 or y = 'a'" so that should work well.

-- Mark