author | wenzelm |
Tue, 14 Aug 2007 13:20:17 +0200 | |
changeset 24259 | c9e05c49d02c |
parent 23850 | f1434532a562 |
child 24421 | acfb2413faa3 |
permissions | -rw-r--r-- |
22308 | 1 |
module Nat = |
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struct |
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type nat = Zero_nat | Suc of nat;; |
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end;; (*struct Nat*) |
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module Codegen = |
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struct |
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type 'a null = {null : 'a};; |
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let null _A = _A.null;; |
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let rec head _B = function x :: xs -> x |
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| [] -> null _B;; |
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let rec null_option = None;; |
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let null_optiona () = ({null = null_option} : ('b option) null);; |
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let rec dummy |
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= head (null_optiona ()) [Some (Nat.Suc Nat.Zero_nat); None];; |
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end;; (*struct Codegen*) |