diff options
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 47 |
1 files changed, 28 insertions, 19 deletions
@@ -33821,31 +33821,40 @@ when written out to the file. Conversely, when the edited file is read back, its newlines are converted to carriage returns, so that multi-line content is handled properly. (See the following section, Multi-Line Mode). -.NP* Undo +.NP* Undo Editing -The listener provides an undo feature. The Ctrl-O editing command will -restore the edit buffer contents and cursor position to the state in which -it was before a previous edit, or previous history navigation. +The listener provides an undo feature. The Ctrl-O command ("old", "oops") +restores the edit buffer contents and cursor position to a previous state. -Undo history is retained between lines. That is, after a line is submitted -with Enter, it is still possible to undo previous edits. Moreover, if a line -is canceled with Ctrl-C, such that it is not recorded in the recall history, it -is still available from the undo history. +There is a single undo history which records up the 200 most recent edit +states. However, the states are associated with history lines, so that it +appears that that undo history has its own, independent undo history. +Undoing the edits in one line has no effect on the undo history of another +line. + +Undo also records edits for lines that has been canceled with Ctrl-C, and are +not entered into the history, making it possible to recall canceled lines. + +The undo history is lost when \*(TX terminates. -Undo is limited to 32 states. Furthermore, the undo history is lost -when \*(TX terminates. +Undo doesn't save and restore previous contents of the clipboard buffer. -Undo doesn't restore previous contents of the clipboard buffer. +There is no redo. When undo removes an edit to restore to a prior edit state, +the removed edit is permanently discarded. -Undo will restore edits made to history lines. It does so unconditionally, -which means that it can introduce edits in the following situation. -When a history line is edited and then sumbitted without navigating to -a different history line, the edit isn't permanent. However, when the -edits are retraced via undo, the restored states -.I are -stored in the history. +Note that if undo is invoked on a historic line, each undo step updates that +history entry instantly to the restored state. This is in contrast +to the way new edits work. New edits are not committed to history until +navigation takes place to a different history line. -There is no redo; undoing is permanent. +Also note that when new edits are performed on a historic line and it is +submitted with Enter without navigating to another line, the undo information +for those edits is retained, and belongs to the newly submitted line. The +historic line hasn't actually been modified, and so it has no new undo +information. However, if a historic line is edited, and then navigation takes +place to a different historic line, then the undo information is committed to +that line, because the modifications to the line have been placed back +in the history entry. .SS* Visual Selection Mode |