History

The last history operation.

The version of the last operation in the history.

The history version is incremented automatically when a new operation is added to the history. Setting the version manually should be done only in rare circumstances when a gap is planned between history versions. When doing so, a gap will be created and the history will accept adding an operation with base version equal to the new history version.

Parameters

version : number

A map that allows retrieving the operations fast based on the given base version.

The gap pairs kept in the <from,to> format.

Anytime the history.version is set to a version larger than history.version + 1, a new <lastHistoryVersion, newHistoryVersion> entry is added to the map.

Operations added to the history.

Holds an information which operation undoes which operation.

Keys of the map are "undoing operations", that is operations that undone some other operations. For each key, the value is an operation that has been undone by the "undoing operation".

Holds all undone operations.

The history version.

Adds an operation to the history and increments the history version.

The operation's base version should be equal to the history version. Otherwise an error is thrown.

Parameters

operation : Operation

Returns

void

Returns operation from the history that bases on given baseVersion.

Parameters

baseVersion : number

Base version of the operation to get.

Returns

undefined | Operation

Operation with given base version or undefined if there is no such operation in history.

Returns operations from the given range of operation base versions that were added to the history.

Note that there may be gaps in operations base versions.

Parameters

[ fromBaseVersion ] : number

Base version from which operations should be returned (inclusive).

toBaseVersion : number

Base version up to which operations should be returned (exclusive). *

Defaults to ...

Returns

Array<Operation>

History operations for the given range, in chronological order.

For given undoingOperation, returns the operation which has been undone by it.

Parameters

undoingOperation : Operation

Returns

undefined | Operation

Operation that has been undone by given undoingOperation or undefined if given undoingOperation is not undoing any other operation.

Checks whether given operation is undoing any other operation.

Parameters

operation : Operation

Operation to check.

Returns

boolean

true if given operation is undoing any other operation, false otherwise.

Checks whether given operation has been undone by any other operation.

Parameters

operation : Operation

Operation to check.

Returns

boolean

true if given operation has been undone any other operation, false otherwise.

Resets the history of operations.

Returns

void

Marks in history that one operation is an operation that is undoing the other operation. By marking operation this way, history is keeping more context information about operations, which helps in operational transformation.

Parameters

undoneOperation : Operation

Operation which is undone by undoingOperation.

undoingOperation : Operation

Operation which undoes undoneOperation.

Returns

void