Class UndoManager

constructor

• new UndoManager(
      disposer: ActionMiddlewareDisposer,
      subtreeRoot: object,
      store?: UndoStore,
      options: undefined | UndoMiddlewareOptions<unknown>,
  ): UndoManager

  Creates an instance of UndoManager. Do not use directly, use undoMiddleware instead.

  Parameters

  • disposer: ActionMiddlewareDisposer
  • subtreeRoot: object
  • Optionalstore: UndoStore
  • options: undefined | UndoMiddlewareOptions<unknown>

  Returns UndoManager

Readonlystore

canRedo

• get canRedo(): boolean

  If redo can be performed (if there is at least one redo action available)

  Returns boolean

canUndo

• get canUndo(): boolean

  If undo can be performed (if there is at least one undo action available).

  Returns boolean

isUndoRecordingDisabled

• get isUndoRecordingDisabled(): boolean

  Returns if undo recording is currently disabled or not for this particular UndoManager.

  Returns boolean

redoLevels

• get redoLevels(): number

  The number of redo actions available.

  Returns number

redoQueue

• get redoQueue(): readonly UndoEvent[]

  The redo stack, where the first operation to redo will be the last of the array. Do not manipulate this array directly.

  Returns readonly UndoEvent[]

undoLevels

• get undoLevels(): number

  The number of undo actions available.

  Returns number

undoQueue

• get undoQueue(): readonly UndoEvent[]

  The undo stack, where the first operation to undo will be the last of the array. Do not manipulate this array directly.

  Returns readonly UndoEvent[]

clearRedo

• clearRedo(): void

  Clears the redo queue.

  Returns void

clearUndo

• clearUndo(): void

  Clears the undo queue.

  Returns void

createGroup

• createGroup(groupName?: string): { continue<T>(fn: () => T): T; end(): void }

  Creates a custom group that can be continued multiple times and then ended.

  Parameters

  • OptionalgroupName: string

    Optional group name.

  Returns { continue<T>(fn: () => T): T; end(): void }

  An API to continue/end the group.

dispose

• dispose(): void

  Disposes the undo middleware.

  Returns void

redo

• redo(): void

  Redoes the previous action. Will throw if there is no action to redo.

  Returns void

undo

• undo(): void

  Undoes the last action. Will throw if there is no action to undo.

  Returns void

withGroup

• withGroup<T>(groupName: string, fn: () => T): T

  Runs a synchronous code block as an undo group. Note that nested groups are allowed.

  Type Parameters

  • T

  Parameters

  • groupName: string

    Group name.
  • fn: () => T

    Code block.

  Returns T

  Code block return value.
• withGroup<T>(fn: () => T): T

  Runs a synchronous code block as an undo group. Note that nested groups are allowed.

  Type Parameters

  • T

  Parameters

  • fn: () => T

    Code block.

  Returns T

  Code block return value.

withGroupFlow

• withGroupFlow<R>(
      groupName: string,
      fn: () => Generator<any, R, any>,
  ): Promise<R>

  Runs an asynchronous code block as an undo group. Note that nested groups are allowed.

  Type Parameters

  • R

  Parameters

  • groupName: string

    Group name.
  • fn: () => Generator<any, R, any>

    Flow function.

  Returns Promise<R>

  Flow function return value.
• withGroupFlow<R>(fn: () => Generator<any, R, any>): Promise<R>

  Runs an asynchronous code block as an undo group. Note that nested groups are allowed.

  Type Parameters

  • R

  Parameters

  • fn: () => Generator<any, R, any>

    Flow function.

  Returns Promise<R>

  Flow function return value.

withoutUndo

• withoutUndo<T>(fn: () => T): T

  Skips the undo recording mechanism for the code block that gets run synchronously inside.

  Type Parameters

  • T

    Code block return type.

  Parameters

  • fn: () => T

    Code block to run.

  Returns T

  The value returned by the code block.