Mercurial > urweb

view demo/sum.ur @ 1242:4ed556678214

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
At loop heads, havoc relations that might be changed by the loop
author Adam Chlipala <adamc@hcoop.net>
date Sat, 17 Apr 2010 14:26:52 -0400
parents 8d3aa6c7cee0
children
line wrap: on
line source
fun sum [fs ::: {Unit}] (fl : folder fs) (x : $(mapU int fs)) =
    @foldUR [int] [fn _ => int]
     (fn [nm :: Name] [rest :: {Unit}] [[nm] ~ rest] n acc => n + acc)
     0 fl x

fun main () = return <xml><body>
  {[sum {}]}<br/>
  {[sum {A = 0, B = 1}]}<br/>
  {[sum {C = 2, D = 3, E = 4}]}
</body></xml>