# let rec polyf x y = if x=0 then 0 else
if (x-1)=0 then (polyf (x-1)) (function z -> z)
else (polyf (x-2)) 0 in polyf 3 1;;
This expression has type int but is here used with type ‘a -> ‘a
# sem (Letrec (Id "polyf", Fun(Id "x", Fun (Id "y",
Ifthenelse(Var (Id "x"), Eint 0,
Ifthenelse (Diff (Var (Id "x"), Eint 1), Appl(Appl (Var (Id "polyf"),
Diff (Var (Id "x"), Eint 1)), Fun (Id "z", Var (Id "z"))),
Appl (Appl (Var (Id "polyf"), Diff (Var (Id "x"), Eint 2)), Eint 0))))),
Appl(Appl(Var (Id "polyf"),Eint 3),Eint 1) )) emptyenv;;
- : eval = Int 0
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