| 11 | | * Define how to make transaction safety possible. |
| 12 | | * |
| | 11 | * Define how to make transaction safety consistent. |
| | 12 | * Create a way to achieve transaction safety for: |
| | 13 | * simple change: |
| | 14 | * a change should be defined as such and put in the list of changes when it is consistent till the time it is to be declared and stored. |
| | 15 | * undo to a change should be done and declared as such when everything is consistently finished otherwise it should not be undone. |
| | 16 | * composite change: |
| | 17 | * a composite change should be constructed of simple changes only when all simple changes are consistent when created. |
| | 18 | * a composite change can be undone if and only if all simple changes are undone one after another otherwise the state should be as if no undo is performed. |
| | 19 | * Provide unit tests for the transaction safety things. |
| | 20 | * Give examples is possible of scenario that implies transaction safety is impossible at this revision so that on later revisions more things are improved. |
