Navigating the Undo Tree in Vim

*usr_32.txt* Nvim VIM USER MANUAL - by Bram Moolenaar The undo tree Vim provides multi-level undo. If you undo a few changes and then make a new change you create a branch in the undo tree. This text is about moving through the branches. |32.1| Undo up to a file write |32.2| Numbering changes |32.3| Jumping around the tree |32.4| Time travelling Next chapter: |usr_40.txt| Make new commands Previous chapter: |usr_31.txt| Exploiting the GUI Table of contents: |usr_toc.txt| ============================================================================== *32.1* Undo up to a file write Sometimes you make several changes, and then discover you want to go back to when you have last written the file. You can do that with this command: > :earlier 1f The "f" stands for "file" here. You can repeat this command to go further back in the past. Or use a count different from 1 to go back faster. If you go back too far, go forward again with: > :later 1f Note that these commands really work in time sequence. This matters if you made changes after undoing some changes. It's explained in the next section. Also note that we are talking about text writes here. For writing the undo information in a file see |undo-persistence|. ============================================================================== *32.2* Numbering changes In section |02.5| we only discussed one line of undo/redo. But it is also possible to branch off. This happens when you undo a few changes and then make a new change. The new changes become a branch in the undo tree. Let's start with the text "one". The first change to make is to append " too". And then move to the first 'o' and change it into 'w'. We then have two changes, numbered 1 and 2, and three states of the text: one ~ | change 1 | one too ~ | change 2 | one two ~ If we now undo one change, back to "one too", and change "one" to "me" we create a branch in the undo tree: one ~ | change 1 | one too ~ / \ change 2 change 3 | | one two me too ~ You can now use the |u| command to undo. If you do this twice you get to "one". Use |CTRL-R| to redo, and you will go to "one too". One more |CTRL-R| takes you to "me too". Thus undo and redo go up and down in the tree, using the branch that was last used. What matters here is the order in which the changes are made. Undo and redo are not considered changes in this context. After each change you have a new state of the text. Note that only the changes are numbered, the text shown in the tree above has no identifier.

This section of the Vim user manual explains how to use Vim's multi-level undo feature, which allows branching in the undo tree when making new changes after undoing previous ones. It covers how to undo up to a file write using ":earlier" and ":later", how changes are numbered, and how to navigate the branches using undo and redo commands. The key is that changes are ordered by when they are made.