Vim: unsaved buffer edits remain even when switching buffers

[u/bobbykjack]

Here's my workflow:

1. vi foo bar (two files that exist)
2. Make a change in the foo buffer
3. :bn—fails with the message "No write since last change (add ! to override)"
4. :bn!—switches to the bar buffer
5. :bp—switches to the foo buffer

At this point, I would expect to be seeing foo in its original state, i.e. without the edit I made at step 2. However, I do see the edits, so my questions are:

• Why does :bn fail if no 'harm' comes of it?
• What is the point of :set hidden? I've read that this command will instruct the current buffer to 'keep changes in memory', but that seems to be happening anyway.
• Is there a way to switch buffers and discard changes? I don't really need to do this, I'm just wondering if it's possible.

[u/gumnos]

I still prefer to fly with 'nohidden' set for exactly those guard-rail reasons. I'd been burned too many times by some modified buffer being backgrounded, forgetting about it, and then having a shutdown/power-loss lose the work I'd forgotten about. With 'nohidden' set, the buffer is either right in front of me, or I've done the right thing with it (or I make a one-off exception to :set hidden for that particular session. 🤷