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
--x_set x2 = ({x = x2}) --still a type error
x_set x2 c = C {x = x2, y = y c} --legal
Which is possibly a reason to stay away from field-update syntax on some
occasions, and therefore not want it to get a more prominent place in
the language if it doesn't deserve it yet.
-Isaac
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