[Haskell-beginners] overload a function

[Britt Anderson]

I would like to have a function that can accept more than one input
type and gives the same back as output. For the different eligible
input types there would be different tests.
An example of the idea would be something like:

test :: a -> Bool -> a

test 0 True = 0
test False True = False
.
.
.

is it obligatory that I create a typeclass for test and then instance
each type that might go in the "a" slot? Because that seems like a lot
of work.

Let me also add a general thank to those of you who support the
beginners' list. I learn something everyday.