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In checking signature subsumption, be sure to try constraints last.
author Adam Chlipala <adam@chlipala.net>
date Thu, 04 Dec 2014 20:22:39 -0500
parents 8d3aa6c7cee0
children
line wrap: on
line source
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 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>