[Haskell-cafe] Defining a containing function on polymorphic list
raeck at msn.com
Mon Dec 22 08:51:15 EST 2008
I am trying to define a containing function to see if a value is one
of the elements within a list which is polymorphic, but failed with the
> contain :: a -> [a] -> Bool
> contain x  = False
> contain x (y:ys) = if x == y then True else contain x ys
it seems that the problem is the 'operator' == does not support a polymorphic check?
Any way can solve the problem? or any alternative solution to achieve the purpose?
It’s the same Hotmail®. If by “same” you mean up to 70% faster.
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the Haskell-Cafe