const n:int = 43

node f(a:int^n; i:int) returns (o:int^n; m:int)
let
     m = a.[i] default 0;
     o = i^n;
tel

node sumdup (a, acc_in:int) returns (o:int; acc_out:int)
let
  acc_out = acc_in + a; 
  o = acc_out;	
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node p(a:int^n) returns (o:int^n)
var acc:int;
let
  (o, acc) = mapfold sumdup <<n>>(a, 0); 
tel