Re: 2 points on language. Continuing

"D. Tweed" <tweed@cs.bris.ac.uk> writes:

On a purely pragmatic note ( :-) ) these optimisations can't necessarily be safely used in three of the four most common cases, namely Int, Float and Double because of the restricted range of intermediates.

While the programmer can't necessarily change ((p-q)+p) to (2*p-q) in the case of Int, the compiler usually can. The compiler can know that on the target machine, Int operations wrap on overflow in the typical way, in which case that's an entirely safe optimization. By the way, are there any Haskell systems where Int does not wrap on overflow? Carl Witty