| author | nipkow |
| Fri, 24 Oct 1997 11:56:12 +0200 | |
| changeset 3984 | 8fc76a487616 |
| parent 2281 | e00c13a29eda |
| permissions | -rw-r--r-- |
| 2281 | 1 |
(* Title: HOL/Integ/Ring.thy |
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ID: $Id$ |
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Author: Tobias Nipkow |
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Copyright 1996 TU Muenchen |
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Bits of rings. |
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Main output: a simplification tactic for commutative rings. |
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*) |
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Ring = Group + |
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(* Ring *) |
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axclass ring < add_agroup, times |
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times_assoc "(x*y)*z = x*(y*z)" |
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distribL "x*(y+z) = x*y + x*z" |
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distribR "(x+y)*z = x*z + y*z" |
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(* Commutative ring *) |
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axclass cring < ring |
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times_commute "x*y = y*x" |
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end |