22 lines
454 B
Text
22 lines
454 B
Text
inductive Expr
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| Var : UInt32 → Expr
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| Val : UInt32 → Expr
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| Add : Expr → Expr → Expr
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open Expr
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def dec (n : UInt32) : UInt32 :=
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if n = 0 then 0 else n-1
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def mkExpr : UInt32 → UInt32 → Expr | n v :=
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if n = 0 then Val v
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else Add (mkExpr (n-1) (v+1)) (mkExpr (n-1) (dec v))
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def eval : Expr → UInt32
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| (Var x) := 0
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| (Val v) := v
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| (Add l r) := eval l + eval r
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def main : IO UInt32 :=
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IO.println (toString $ eval (mkExpr 26 1)) *>
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pure 0
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