Isaac Dupree
Jon Fairbairn wrote:
Parenthesis around updates would make them into functions, ie ({a=1,b=2,...}) would mean the same as (\d -> d{a=1,b=2,...}), but be more concise.
yes it is, however field updates are occasionally slightly annoying, since they can't change something's type at all, IIRC. Say, data C nx ny = C { x :: nx, y :: ny } x_set :: nx2 -> C nx1 ny -> C nx2 ny --x_set x2 c = c {x = x2} --type error
If that were the case, it would be a serious wart that needed to be addressed. However, implementation would be fairly straightforward as an "extension" is already present in ghc: let x_set x2 c = c{x=x2} :t x_set x_set :: nx -> C t ny -> C nx ny ;-) (or did I misunderstand you?) -- Jón Fairbairn Jon.Fairbairn@cl.cam.ac.uk