| author | haftmann |
| Tue, 18 Sep 2007 10:44:02 +0200 | |
| changeset 24628 | 33137422d7fd |
| parent 24421 | acfb2413faa3 |
| child 25056 | 743f3603ba8b |
| permissions | -rw-r--r-- |
| 22308 | 1 |
module Nat = |
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struct |
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type nat = Suc of nat | Zero_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 null_option () = ({null = None} : ('a option) null);;
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let rec dummy |
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= head (null_option ()) [Some (Nat.Suc Nat.Zero_nat); None];; |
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end;; (*struct Codegen*) |