next up previous contents index
Next: The Redo Button: Redo Up: The Modify Menu: Modify Previous: The Modify Menu: Modify   Contents   Index

The Undo Button: Undo Operation

The Undo button in the Modify Menu reverses the operations performed in the current cell. These operations can be undone as long as the present cell is the current cell. Undone operations can be redone with the Redo command. Pressing the Tab key has the same effect as clicking on the Undo button, and Shift-Tab is equivalent to Redo.

By default, the last 25 operations can be undone. This can be changed with the variable UndoListLength, which can be set to a non-negative integer with the !set command. This sets the number of operations that are remembered. If set to zero, the list length is unlimited.

When Xic is waiting for text input to the prompt line, the Undo and Redo commands are disabled.

Stephen R. Whiteley 2017-03-22