22 Jul
2008
22 Jul
'08
1:33 p.m.
On Tue, Jul 22, 2008 at 10:27 AM, Neil Mitchell
Hi
Why such a style doesn't work, so I must write ugly code like that:
outStanza a | (isMessage a) = outMessage a | (isPresence a) = outPresence a | (isIQ a) = outIQ a
You can make it slightly prettier, since the brackets are not necessary:
outStanza a | isMessage a = outMessage a | isPresence a = outPresence a | isIQ a = outIQ a
Also, if it really is in that format, maybe you can write something like: switch v pairs = maybe (error "no match") ($v) (lookupWith ($v) pairs) And then you can write the list point-free, though you don't get the nice guard syntax. I guess lookupWith must be one of my local functions, but it's easy to write too.