Question

How can I pare down my buffer list to only include buffers that are currently open in a window/tab?

When I’ve been running Vim for a long time, the list of buffers revealed by the :ls command is too large to work with. Ideally, I would like to delete all of the buffers which are not currently visible in a tab or window by running a custom command such as :Only. Can anybody suggest how to achieve this?

It looks like the :bdelete command can accept a list of buffer numbers, but I’m not sure how to translate the output from :ls to a format that can be consumed by the :bdelete command. Any help would be appreciated.

Clarification

Lets say that in my Vim session I have opened 4 files. The :ls command outputs:

:ls
1  a   "abc.c"
2  h   "123.c"
3  h   "xyz.c"
4  a   "abc.h"

Buffer 1 is in the current tab, and and buffer 4 is in a separate tab, but
buffers 2 and 3 are both hidden. I would like to run the command :Only, and
it would wipe buffers 2 and 3, so the :ls command would output:

:ls
1  a   "abc.c"
4  a   "abc.h"

This example doesn’t make the proposed :Only command look very useful, but
if you have a list of 40 buffers it would be very welcome.

Answer 1

I’ve adapted Laurence Gonslaves solution.

command! -nargs=* Only call CloseHiddenBuffers()
function! CloseHiddenBuffers()
  " figure out which buffers are visible in any tab
  let visible = {}
  for t in range(1, tabpagenr('$'))
    for b in tabpagebuflist(t)
      let visible[b] = 1
    endfor
  endfor
  " close any buffer that are loaded and not visible
  let l:tally = 0
  for b in range(1, bufnr('$'))
    if bufloaded(b) && !has_key(visible, b)
      let l:tally += 1
      exe 'bw ' . b
    endif
  endfor
  echon "Deleted " . l:tally . " buffers"
endfun

I changed it to use bwipeout instead of bdelete, and added the message to show how many buffers have been removed.