replacing words in vim

https://vim.help/12-clever-tricks#12.7

By combining several commands you can make Vim do nearly everything. In this chapter a number of useful combinations will be presented. This uses the commands introduced in the previous chapters and a few more.

Clever tricks

Replace a word

The substitute command can be used to replace all occurrences of a word with another word:

:%s/four/4/g

The % range means to replace in all lines. The g flag at the end causes all words in a line to be replaced.

This will not do the right thing if your file also contains thirtyfour. It would be replaced with thirty4. To avoid this, use the \< item to match the start of a word:

:%s/\<four/4/g

Obviously, this still goes wrong on fourteen. Use \> to match the end of a word:

:%s/\<four\>/4/g

If you are programming, you might want to replace four in comments, but not in the code. Since this is difficult to specify, add the c flag to have the substitute command prompt you for each replacement:

:%s/\\<four\\>/4/gc

Replacing in several files

Suppose you want to replace a word in more than one file. You could edit each file and type the command manually. It's a lot faster to use record and playback.

Let's assume you have a directory with C++ files, all ending in .cpp. There is a function called GetResp that you want to rename to GetAnswer.

vim \*.cpp

Start Vim, defining the argument list to contain all the C++ files. You are now in the first file.

qq

Start recording into the q register

:%s/\<GetResp\>/GetAnswer/g

Do the replacements in the first file.

:wnext

Write this file and move to the next one.

q

Stop recording.

@q

Execute the q register. This will replay the substitution and :wnext. You can verify that this doesn't produce an error message.

999@q

Execute the q register on the remaining files.

At the last file you will get an error message, because :wnext cannot move to the next file. This stops the execution, and everything is done.

When playing back a recorded sequence, an error stops the execution. Therefore, make sure you don't get an error message when recording.

There is one catch: If one of the .cpp files does not contain the word GetResp, you will get an error and replacing will stop. To avoid this, add the e flag to the substitute command:

:%s/\<GetResp\>/GetAnswer/ge

The e flag tells :substitute that not finding a match is not an error.