Mercurial > urweb

fun sum [t] (_ : num t) [fs ::: {Unit}] (fl : folder fs) (x : $(mapU t fs)) =
    foldUR [t] [fn _ => t]
    (fn [nm :: Name] [rest :: {Unit}] [[nm] ~ rest] n acc => n + acc)
    zero [fs] fl x

fun main () = return <xml><body>
  {[sum {A = 0, B = 1}]}<br/>
  {[sum {C = 2.1, D = 3.2, E = 4.3}]}
</body></xml>
author	Adam Chlipala <adamc@hcoop.net>
date	Tue, 15 Dec 2009 12:26:00 -0500
parents	669ac5e9a69e
children	8d3aa6c7cee0