Crate undo

An undo-redo library.

It is an implementation of the command pattern, where all modifications are done by creating objects that applies the modifications. All objects knows how to undo the changes it applies, and by using the provided data structures it is easy to apply, undo, and redo changes made to a target.

Features

• Action provides the base functionality for all actions. Multiple Actions can be merged into a single action by implementing the merge method on the action. This allows smaller actions to be used to build more complex operations, or smaller incremental changes to be merged into larger changes that can be undone and redone in a single step.
• Record provides basic stack based undo-redo functionality.
• History provides full tree based undo-redo functionality.
• Queue and checkpoint functionality is supported for both Record and History.
• The target can be marked as saved to disk and the user will be notified when it changes.
• The amount of changes being tracked can be configured by the user so only the N most recent changes are stored.
• Configurable display formatting using the display structures.

Cargo Feature Flags

Name	Default	Description
colored		Enables colored output when visualizing the display structures.
serde		Enables serialization and deserialization.

Re-exports

• pub use history::History;
• pub use record::Record;

Modules

• history
  A history tree of actions.
• record
  A linear record of actions.

Structs

• Any
  Any action type.
• FromFn
  Action made from a function.
• Join
  Two actions joined together.
• Nop
  Default slot that does nothing.
• TryFromFn
  Action made from a fallible function.
• TryJoin
  Joins two fallible actions together.

Enums

• Merged
  Says if the action have been merged with another action.
• Signal
  The signal used for communicating state changes.

Traits

• Action
  Base functionality for all actions.
• Slot
  Use this to receive signals from History or Record.