Inferring types

[Jan Carlson]

Hi!

I'm intrigued by the following Haskell behaviour:

The type of (+) is

(+) :: (Num a) => a -> a -> a

Now, if I define

p = (+)

the type of p is inferred to be

p :: Integer -> Integer -> Integer

How come?

I guess the answer can be found somewhere in the Haskell report, but I'd
really appreciate just a rough description of the issue.

Thanks in advance.

Jan Carlson