src/HOL/ex/Guess.thy
 author bulwahn Fri Oct 21 11:17:14 2011 +0200 (2011-10-21) changeset 45231 d85a2fdc586c parent 41460 ea56b98aee83 child 58889 5b7a9633cfa8 permissions -rw-r--r--
replacing code_inline by code_unfold, removing obsolete code_unfold, code_inline del now that the ancient code generator is removed
```     1 (*
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```     2     Author:     Makarius
```
```     3 *)
```
```     4
```
```     5 header {* Proof by guessing *}
```
```     6
```
```     7 theory Guess
```
```     8 imports Main
```
```     9 begin
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```    10
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```    11 lemma True
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```    12 proof
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```    13
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```    14   have 1: "\<exists>x. x = x" by simp
```
```    15
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```    16   from 1 guess ..
```
```    17   from 1 guess x ..
```
```    18   from 1 guess x :: 'a ..
```
```    19   from 1 guess x :: nat ..
```
```    20
```
```    21   have 2: "\<exists>x y. x = x & y = y" by simp
```
```    22   from 2 guess apply - apply (erule exE conjE)+ done
```
```    23   from 2 guess x apply - apply (erule exE conjE)+ done
```
```    24   from 2 guess x y apply - apply (erule exE conjE)+ done
```
```    25   from 2 guess x :: 'a and y :: 'b apply - apply (erule exE conjE)+ done
```
```    26   from 2 guess x y :: nat apply - apply (erule exE conjE)+ done
```
```    27
```
```    28 qed
```
```    29
```
```    30 end
```