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23 lines
570 B
OCaml
23 lines
570 B
OCaml
let rec i2n n =
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match n with
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| 0 -> O
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| _ -> S (i2n (n - 1))
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let interp c =
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let h : (nat, nat) Hashtbl.t = Hashtbl.create 0 in
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Hashtbl.add h (i2n 0) (i2n 2);
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Hashtbl.add h (i2n 1) (i2n 1);
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Hashtbl.add h (i2n 2) (i2n 8);
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Hashtbl.add h (i2n 3) (i2n 6);
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let rec interp' (c : 'a cmd) : 'a =
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match c with
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| Return v -> v
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| Bind (c1, c2) -> interp' (c2 (interp' c1))
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| Read a ->
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Obj.magic (try
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Hashtbl.find h a
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with Not_found -> O)
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| Write (a, v) -> Obj.magic (Hashtbl.replace h a v)
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in h, interp' c
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