On Thu, Nov 12, 2009 at 5:40 PM, Nathan M. Holden
This is just a theory, but in my (limited) experience, GHCi is willing to guess at the type of values, where at functions (explicitly or implicitly typed) it can't guess.
In your original function, it multiplied a number (Num a) => a by an Int, therefor it must be Int -> Int (because you can't multiply a Double by an Int, don't be crazy.
That is not the problem : as the rest of your message acknowledge 2 is not an Int, it is of type (Num a) => a. The issue rest squarely with the fact that the binding f1 don't have parameter expressed on the left side of the "=", thus the monomorphism restriction kicks in (as alluded, probably, by your first paragraph) and GHC has to use the defaulting rules to find a monomorphic type for f1. -- Jedaï