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Start of kind polymorphism, up to the point where demo/hello elaborates with updated Basis/Top
author Adam Chlipala <adamc@hcoop.net>
date Sun, 22 Feb 2009 16:10:25 -0500
parents 6a0e54400805
children f4f2b09a533a
line wrap: on
line source
fun sum (fs ::: {Unit}) (x : $(mapUT int fs)) =
    foldUR [int] [fn _ => int]
    (fn (nm :: Name) (rest :: {Unit}) [[nm] ~ rest] n acc => n + acc)
    0 [fs] x

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