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comparison demo/tcSum.ur @ 417:e0e9e9eca1cb

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Fix nasty de Bruijn substitution bug; TcSum demo
author Adam Chlipala <adamc@hcoop.net>
date Thu, 23 Oct 2008 12:58:35 -0400
parents
children 6c4643880df5
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416:679b2fbbd4d0 417:e0e9e9eca1cb
1 fun sum (t ::: Type) (_ : num t) (fs ::: {Unit}) (x : $(mapUT t fs)) =
2 foldUR [t] [fn _ => t]
3 (fn (nm :: Name) (rest :: {Unit}) [[nm] ~ rest] n acc => n + acc)
4 zero [fs] x
5
6 fun main () = return <xml><body>
7 {[sum {A = 0, B = 1}]}<br/>
8 {[sum {C = 2.1, D = 3.2, E = 4.3}]}
9 </body></xml>