On Tuesday 29 June 2010 12:50:34, Ketil Malde wrote: > Daniel Fischer <daniel.is.fisc...@web.de> writes: > >> An important point of a powerful type system is to model your program > >> so that only sensible code is legal. > > > > That would be an awesomely powerful type system :) > > Heh. But while we're waiting for it, we can try to use what we got to > eliminate as much non-sensical code as possible.
+1 > > ...which is a worry my implementation removed by letting the user decide > through partial application. > Aye. > > For a symmetric relation, you needn't care. > > But the docs (are interpreted to) say equivalence relation, so woe > betide you if you give it a symmetric but non-transitive or > non-reflexive function! > > deleteBy (\x y -> abs (x-y) == 2) 5 [1..5] grin > > Anyway: I guess the point here is that if all 'deleteBy f x ys' does > with arguments f and x is apply f to x and then use the result, we might > as well feed it that result and eliminate a lot of uncertainity as well > as some documentation all too few of us bother to read. > Full agreement! _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
