Setting buffer specific variables in Vim

Question

I'm trying to set a buffer-local variable to a global variable if the local variable is not defined using the following autocmd

au BufEnter * if !exists('b:Variable') | let b:Variable = g:Variable | endif

However, b:Variable is not getting defined. What am I doing incorrect here?

EDIT: To rephrase/clarify, b:Variable is being used in the file. The error is that b:Variable is not defined.

What's the error message? Did you define the g:Variable?

kev
– kev

2012-07-05 02:32:03 +00:00
Commented Jul 5, 2012 at 2:32 — kev
– kev, Commented Jul 5, 2012 at 2:32

Habi · Accepted Answer · 2012-07-05 19:54:47Z

4

First of all, your autocommand is correct. It should work.

I see some reasons why it could fail:

g:Variable is not defined
Events are disabled, see :help eventignore (this is unlikely)
The autocommand-feature is not supported by your vim version (this is unlikely too). :version must list +autocmd.
My favorite: The autocommand is not sourced. Are you sure that your autocommand is active?

What does

:verbose autocmd BufEnter

say? If your autocommand is not listed, it is not active.

Or try something that is simpler and that gives direct feedback to see if autocommands with BufEnter generally work. For example

:au BufEnter * echom "Buffer Entered"

edited Jul 5, 2012 at 19:54

answered Jul 5, 2012 at 19:39

Habi

3,31027 silver badges24 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

kshenoy Over a year ago

Ok, I was actually using b:Variable inside the file and BufEnter is executed after the Buffer is entered. Hence, I was getting the errors. What I actually wanted was something along the lines of BufEnterPre. Replaced BufEnter in the autocmd with BufReadPre and now everything is humming along quietly :)

starball · Accepted Answer · 2023-05-03 10:21:09Z

0

Actually, BufReadPre doesn't cover all the cases - it triggers only for existing files, when those are read into the buffer. To have autocmd trigger also for new files, one can compose BufReadPre with BufNew like this:

augroup ale_linters
    autocmd!
    autocmd BufNew,BufReadPre * if !exists('b:ale_linters') | let b:ale_linters = 'all' | endif
augroup end

edited May 3, 2023 at 10:21

starball♦

59.5k52 gold badges314 silver badges1k bronze badges

answered May 3, 2023 at 9:51

limitedeternity

2024 silver badges9 bronze badges

Collectives™ on Stack Overflow

Setting buffer specific variables in Vim

2 Answers 2

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related