How to truncate all lines at a certain length?

Question

Much like this question, I've failed to put this together successfully on my own.

I want to truncate lines in my file so that no line is over 100 characters in length.

I can go to position 100 on each line and execute a d$ (or just a D), but what command will do this for every line in the file? Note: some lines are less than 100 characters.

Do a macro if you know how to do it for a single line. Or smth like :%normal 100|d$ — Maxim Kim, Nov 14 '19 at 19:13
@MaximKim, :%norm 100|D will not work because 100| will just move to the end of the line on lines shorter than 100 chars. Meaning it will delete the last character for those lines. — Peter Rincker, Nov 14 '19 at 19:15

Peter Rincker · Accepted Answer · 2019-11-14T19:38:09.680

Using a substitution

:%s/.\{100}\zs.*//

Find 100 characters, .\{100} then start the match, \zs, and select the rest of the line, .*. Replace the match with nothing.

For more help see:

:h :s
:h /\.
:h /\{
:h \zs
:h /\*

Using filter

:%!cut -c 1-100

Use filter, :!, with a range of the entire file, %. This will take the entire buffer and pass the text as stdin to cut and replace the buffer text with the stdout of our command. Use -c 1-100 to get the first 100 characters.

For more help see:

:!
:range

Using `:normal`

:%norm! v99lyVp

For every line, %, run command, {cmd} via :normal! {cmd}. Select and yank the first 100 characters via v99ly. Then replace the entire line, V with the just yanked 100 characters, p.

In theory, it would be nice to use 101|D, however 101| will just move to the end of the line for too short of lines. This will result short lines losing their trailing character. | also jumps by screen columns so could be messed up by indention.

For more help see:

:h :norm
:h :range
:h v_p

Excellent, thank you very, very much! – Davo Nov 14 '19 at 19:26 — Davo, Nov 14 '19 at 19:26

How to truncate all lines at a certain length?

1 Answers1

Using a substitution

Using filter

Using :normal

Using `:normal`