| author | wenzelm | 
| Fri, 18 Jul 1997 13:51:28 +0200 | |
| changeset 3531 | f6cc9112f4e9 | 
| parent 2907 | 0e272e4c7cb2 | 
| permissions | -rw-r--r-- | 
| 1247 | 1 | (* Title: Group.thy | 
| 2 | ID: $Id$ | |
| 3 | Author: Markus Wenzel, TU Muenchen | |
| 4 | *) | |
| 5 | ||
| 2907 | 6 | Group = Sigs + Fun + | 
| 1247 | 7 | |
| 8 | (* semigroups *) | |
| 9 | ||
| 10 | axclass | |
| 11 | semigroup < times | |
| 12 | assoc "(x * y) * z = x * (y * z)" | |
| 13 | ||
| 14 | ||
| 15 | (* groups *) | |
| 16 | ||
| 17 | axclass | |
| 2907 | 18 | group < one, inverse, semigroup | 
| 1247 | 19 | left_unit "1 * x = x" | 
| 2907 | 20 | left_inverse "inverse x * x = 1" | 
| 1247 | 21 | |
| 22 | ||
| 23 | (* abelian groups *) | |
| 24 | ||
| 25 | axclass | |
| 26 | agroup < group | |
| 27 | commut "x * y = y * x" | |
| 28 | ||
| 29 | end |