30 Dec
2008
30 Dec
'08
1:24 a.m.
Are there anyway to express the "iterating" of a user-defined data type in Haskell? For example, in
data Shape = Square | Circle | Triangle
how can I 'iterate' them and apply them all to the same function without indicating them explicitly? such as [func Square, func Circle, func Triangle]. Can I use a form similar to the following case in a list instead:
Numbers = [1,2,3,4,5]
[func x | x <- Numbers ]
Actually what I want is to obtain all the possible values of a data type (Shape). Thank you very much! Best wishes, Raeck