also safety, and "theorems for free". Then there are other properties which are obvious (to a programmer) in a Haskell program which get buried in
equivalent C(++) program, e.g., that every member of a data structure is traversed in a fold ("no early exits"). Many of these things hinge on
On Thu, 26 Jul 2001, Frank Atanassow wrote: the the
typing of a program, which is inferred and checked for you, so there is less of a burden on conscientious programmers.
I'm being terribly unfair here; this was probably just a simple slip when writing a hurried e-mail but if you mean what I think you mean about the fold: undefd = undefd f y x|y=='a' = "finished" |otherwise = y:x g xs = foldr f "" xs Main> g ('a':undefd) "finished" shows that folds can exit early; if it didn't it'd black hole forever. ___cheers,_dave________________________________________________________ www.cs.bris.ac.uk/~tweed/pi.htm |tweed's law: however many computers email: tweed@cs.bris.ac.uk | you have, half your time is spent work tel: (0117) 954-5250 | waiting for compilations to finish.