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diff 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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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demo/tcSum.ur	Thu Oct 23 12:58:35 2008 -0400
@@ -0,0 +1,9 @@
+fun sum (t ::: Type) (_ : num t) (fs ::: {Unit}) (x : $(mapUT t fs)) =
+    foldUR [t] [fn _ => t]
+    (fn (nm :: Name) (rest :: {Unit}) [[nm] ~ rest] n acc => n + acc)
+    zero [fs] x
+
+fun main () = return <xml><body>
+  {[sum {A = 0, B = 1}]}<br/>
+  {[sum {C = 2.1, D = 3.2, E = 4.3}]}
+</body></xml>