Ur/Web: demo/sum.ur annotate

Kind-polymorphic [fst] and friends

author	Adam Chlipala <adamc@hcoop.net>
date	Thu, 26 Feb 2009 16:16:54 -0500
parents	03ab853c8e4b
children	aa2290c32ce2

rev	line source
adamc@632	1 fun sum (fs ::: {Unit}) (fl : folder fs) (x : $(mapUT int fs)) =
adamc@411	2 foldUR [int] [fn _ => int]
adamc@411	3 (fn (nm :: Name) (rest :: {Unit}) [[nm] ~ rest] n acc => n + acc)
adamc@632	4 0 [fs] fl x
adamc@411	5
adamc@411	6 fun main () = return <xml><body>
adamc@633	7 {[sum {}]}<br/>
adamc@633	8 {[sum {A = 0, B = 1}]}<br/>
adamc@633	9 {[sum {C = 2, D = 3, E = 4}]}
adamc@411	10 </body></xml>

Mercurial > urweb