LuaUndoRedoStack

The undo queue for a player. The term item_index refers to the index of an undo item in the queue, while action_index refers to the index of one of the individual actions that make up an undo item.

Items are added to the undo queue through player actions and Lua methods that emulate player actions like LuaEntity::order_upgrade.

Attributes

player_index

• Read: uint32
• Write: unknown
• Optional: false

The index of the player to whom this stack belongs to.

valid

• Read: boolean
• Write: unknown
• Optional: false

Is this object valid? This Lua object holds a reference to an object within the game engine. It is possible that the game-engine object is removed whilst a mod still holds the corresponding Lua object. If that happens, the object becomes invalid, i.e. this attribute will be false. Mods are advised to check for object validity if any change to the game state might have occurred between the creation of the Lua object and its access.

object_name

• Read: string
• Write: unknown
• Optional: false

The class name of this object. Available even when valid is false. For LuaStruct objects it may also be suffixed with a dotted path to a member of the struct.

Methods

get_undo_item

LuaUndoRedoStack.get_undo_item(index: uint32) -> Array<UndoRedoAction>

Call As

undoRedoStack.get_undo_item(index)

Call Convention

• takes_table: false
• table_optional: false

Gets an undo item from the undo stack.

Parameters

• index: uint32 — The index of the undo item to get, ordered from most recent to oldest.

Returns

• Array<UndoRedoAction>

get_undo_item_count

LuaUndoRedoStack.get_undo_item_count() -> uint32

Call As

undoRedoStack.get_undo_item_count()

Call Convention

• takes_table: false
• table_optional: false

The number undo items in the undo stack.

Returns

• uint32

remove_undo_item

LuaUndoRedoStack.remove_undo_item(index: uint32)

Call As

undoRedoStack.remove_undo_item(index)

Call Convention

• takes_table: false
• table_optional: false

Removes an undo item from the undo stack.

Parameters

• index: uint32 — The index of the undo item to remove, ordered from most recent to oldest.

remove_undo_action

LuaUndoRedoStack.remove_undo_action(item_index: uint32, action_index: uint32)

Call As

undoRedoStack.remove_undo_action(item_index, action_index)

Call Convention

• takes_table: false
• table_optional: false

Removes an undo action from the specified undo item on the undo stack.

Parameters

• item_index: uint32 — The index of the undo item to change, ordered from most recent to oldest.
• action_index: uint32 — The index of the undo action to remove.

get_redo_item

LuaUndoRedoStack.get_redo_item(index: uint32) -> Array<UndoRedoAction>

Call As

undoRedoStack.get_redo_item(index)

Call Convention

• takes_table: false
• table_optional: false

Gets an undo item from the redo stack.

Parameters

• index: uint32 — The index of the item to get, ordered from most recent to oldest.

Returns

• Array<UndoRedoAction>

get_redo_item_count

LuaUndoRedoStack.get_redo_item_count() -> uint32

Call As

undoRedoStack.get_redo_item_count()

Call Convention

• takes_table: false
• table_optional: false

The number of undo items in the redo stack.

Returns

• uint32

remove_redo_item

LuaUndoRedoStack.remove_redo_item(index: uint32)

Call As

undoRedoStack.remove_redo_item(index)

Call Convention

• takes_table: false
• table_optional: false

Removes an undo item from the redo stack.

Parameters

• index: uint32 — The index of the undo item to remove, ordered from most recent to oldest.

remove_redo_action

LuaUndoRedoStack.remove_redo_action(item_index: uint32, action_index: uint32)

Call As

undoRedoStack.remove_redo_action(item_index, action_index)

Call Convention

• takes_table: false
• table_optional: false

Removes an undo action from the specified undo item on the redo stack.

Parameters

• item_index: uint32 — The index of the undo item to change, ordered from most recent to oldest.
• action_index: uint32 — The index of the undo action to remove.

get_undo_tags

LuaUndoRedoStack.get_undo_tags(item_index: uint32, action_index: uint32) -> Tags

Call As

undoRedoStack.get_undo_tags(item_index, action_index)

Call Convention

• takes_table: false
• table_optional: false

Gets all tags for the given undo action.

Parameters

• item_index: uint32 — The index of the undo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the undo action.

Returns

• Tags

get_undo_tag

LuaUndoRedoStack.get_undo_tag(item_index: uint32, action_index: uint32, tag_name: string) -> AnyBasic

Call As

undoRedoStack.get_undo_tag(item_index, action_index, tag_name)

Call Convention

• takes_table: false
• table_optional: false

Gets the tag with the given name from a specific undo item action, or nil if it doesn't exist.

Parameters

• item_index: uint32 — The index of the undo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the undo action.
• tag_name: string — The name of the tag to get.

Returns

• AnyBasic

set_undo_tag

LuaUndoRedoStack.set_undo_tag(item_index: uint32, action_index: uint32, tag_name: string, tag: AnyBasic)

Call As

undoRedoStack.set_undo_tag(item_index, action_index, tag_name, tag)

Call Convention

• takes_table: false
• table_optional: false

Sets a new tag with the given name and value on the specified undo item action.

Parameters

• item_index: uint32 — The index of the undo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the undo action.
• tag_name: string — The name of the tag to set.
• tag: AnyBasic — The contents of the new tag.

remove_undo_tag

LuaUndoRedoStack.remove_undo_tag(item_index: uint32, action_index: uint32, tag: string) -> boolean

Call As

undoRedoStack.remove_undo_tag(item_index, action_index, tag)

Call Convention

• takes_table: false
• table_optional: false

Removes a tag with the given name from the specified undo item.

Parameters

• item_index: uint32 — The index of the undo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the undo action.
• tag: string — The name of the tag to remove.

Returns

• boolean — Whether the tag existed and was successfully removed.

get_redo_tags

LuaUndoRedoStack.get_redo_tags(item_index: uint32, action_index: uint32) -> Tags

Call As

undoRedoStack.get_redo_tags(item_index, action_index)

Call Convention

• takes_table: false
• table_optional: false

Gets all tags for the given redo action.

Parameters

• item_index: uint32 — The index of the redo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the redo action.

Returns

• Tags

get_redo_tag

LuaUndoRedoStack.get_redo_tag(item_index: uint32, action_index: uint32, tag_name: string) -> AnyBasic

Call As

undoRedoStack.get_redo_tag(item_index, action_index, tag_name)

Call Convention

• takes_table: false
• table_optional: false

Gets the tag with the given name from a specific redo item action, or nil if it doesn't exist.

Parameters

• item_index: uint32 — The index of the redo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the redo action.
• tag_name: string — The name of the tag to get.

Returns

• AnyBasic

set_redo_tag

LuaUndoRedoStack.set_redo_tag(item_index: uint32, action_index: uint32, tag_name: string, tag: AnyBasic)

Call As

undoRedoStack.set_redo_tag(item_index, action_index, tag_name, tag)

Call Convention

• takes_table: false
• table_optional: false

Sets a new tag with the given name and value on the specified redo item action.

Parameters

• item_index: uint32 — The index of the redo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the redo action.
• tag_name: string — The name of the tag to set.
• tag: AnyBasic — The contents of the new tag.

remove_redo_tag

LuaUndoRedoStack.remove_redo_tag(item_index: uint32, action_index: uint32, tag: string) -> boolean

Call As

undoRedoStack.remove_redo_tag(item_index, action_index, tag)

Call Convention

• takes_table: false
• table_optional: false

Removes a tag with the given name from the specified redo item.

Parameters

• item_index: uint32 — The index of the redo item, ordered from most recent to oldest.
• action_index: uint32 — The index of the redo action.
• tag: string — The name of the tag to remove.

Returns

• boolean — Whether the tag existed and was successfully removed.