Re: A question about Hugs 98

[Erik Meijer]

> general f x = f x x
> double = general (+)
> 
> The system infers the types:
> 
> general:: (a -> a -> b) -> a -> b
> general (+):: Num a => a -> a
> 
> but
> double:: Integer -> Integer
> 
> 
> How is this possible?
> 
> Thank you in advance!

Dreaded monomorphism restriction :-)

Try defining double as

double x = general (+) x

Alas, that's the way it is.

Erik