vim-scripts / join.vim Goto Github PK

This is a mirror of http://www.vim.org/scripts/script.php?script_id=2766

ATTENTION: Vim 7.3 contains a bugfix, so this plugin isn't needed anymore!

This plugin tries to implement a different method for joining lines. This is,
because the :join command from within vim suffers from a serious performance
issue, if you are trying to join many lines (>1000).

This has been discussed on the vim development mailing list (see
http://thread.gmane.org/gmane.editors.vim.devel/22065) as well as on the vim
user mailing list (see http://thread.gmane.org/gmane.editors.vim/80304).

There has also been a patch proposed, to improve the algorithm used by :join.
This patch is available at http://repo.or.cz/w/vim_extended.git, but this
means, you'll have to build and patch your vim manually (you can't use it with
a prebuilt vim).

Until this patch is accepted and incorporated into mainline vim, this plugin
tries to improve the joining algorithm by the method mentioned in the user
mailinglist above. It basically works by breaking up the join algorithm into
smaller pieces and joining the smaller pieces together. This may have an
impact on memory usage, though.

                                                              *Join-benchmark*
For reference I include some timings, joining many lines:

      Lines joined      :%join      |      :%Join
        25.000           3,305s     |      0,240s
        50.000          13,667s     |      0,336s
       100.000          64,140s     |      0,588s
       200.000         331,410s     |      1,431s
     1.000.000            -[1]      |      7,419s

[1] benchmarking was aborted after 53 Minutes (after which only about 480.000
lines have been joined).

Please also note, that using a substitute command does not prove to be faster.
It also suffers from the performance impact.

Also note, that really the best way to remove '\n' on a file with millions
of lines is using tr:

~$ tr -d '\n' <large_file >output_file

2. Usage                                                          *Join-usage*

:[range]J[oin][!]
                        Join [range] lines.  Same as "J", except with [!]
                        the join does not insert or delete any spaces.
                        The default behavior is to join the current line
                        with the line below it.

:[range]J[oin][!] {count}
                        Join {count} lines, starting with [range] (default:
                        current line |cmdline-ranges|).  Same as "J", except
                        with [!] the join does not insert or delete any
                        spaces.


You should be able to use :Join as drop in replacement for :join. It behaves
exactly like :join and understands it's syntax, with the exception of 1 point:

1) :Join does not accept the use of [flags] as |:join| does.

If you want the J command to call :Join, you can use something like:
:nmap J :Join<CR>
to have J call :Join in normal mode and
:vmap J :Join<CR>

                                                            *Join-differences*
3. Differences

This plugin has been made to make :Join and :join behave almost identically.
If there are further differences than those described at |Join-usage|, I am
interested at any bug describing exactly what went wrong, so I can fix this.
Please send any bug report to the mail address mentioned at the top of this
page.