On 12/12/2012 11:20 AM, Eelco Dolstra wrote: > Hi, > > On 12/12/12 17:15, Shea Levy wrote: > >>>> The elem library function evaluates all list elements instead of >>>> returning "true" after finding a matching element. >>> Sure about that? This seems lazy enough: >>> >>> elem = >>> builtins.elem or >>> (x: list: fold (a: bs: x == a || bs) false list); >>> >> Shouldn't the bs come first? i.e. (a: bs: bs || x == a)? > Not if you want to check from left to right. >
Huh? I didn't change the argument order, this is still a left fold. this just short-circuits the eval of (x == a) when bs is true. _______________________________________________ nix-dev mailing list [email protected] http://lists.science.uu.nl/mailman/listinfo/nix-dev
