Lennart Augustsson wrote:
I think your first try looks good. [snip] ... addPoly1 p1@(p1h@(Nom p1c p1d):p1t) p2@(p2h@(Nom p2c p2d):p2t) | p1d == p2d = Nom (p1c + p2c) p1d : addPoly1 p1t p2t | p1d < p2d = p1h : addPoly1 p1t p2 | p1d > p2d = p2h : addPoly1 p1 p2t ...
The last comparison is redundant (this was in the original version too) because p1d > p2d is implied (certainly for this case where p1d, p2d::Int) by the fall through from not satisfying == and < so how about: addPoly1 p1@(p1h@(Nom p1c p1d):p1t) p2@(p2h@(Nom p2c p2d):p2t) | p1d == p2d = Nom (p1c + p2c) p1d : addPoly1 p1t p2t | p1d < p2d = p1h : addPoly1 p1t p2 | otherwise = p2h : addPoly1 p1 p2t Regards, Brian. -- Logic empowers us and Love gives us purpose. Yet still phantoms restless for eras long past, congealed in the present in unthought forms, strive mightily unseen to destroy us. http://www.metamilk.com