Vim:Getting rid of ^M With Vim

1. Using Regular Expressions

Ripped gratuitously from http://vim.sourceforge.net/tips/tip.php?tip_id=26
If you work in a mixed environment you will often open files that have ^M's in them. An example would be this:

import java.util.Hashtable; ^M
import java.util.Properties; ^M
import java.io.IOException; ^M
import org.xml.sax.AttributeList; ^M
import org.xml.sax.HandlerBase; ^M
import org.xml.sax.SAXException;^M
 
/**^M
  * XMLHandler: This class parses the elements contained^M
  * within a XML message and builds a Hashtable^M
**/^M

Notice that some programs are not consistent in the way they insert the line breaks so you end up with some lines that have both a carrage return and a ^M and some lines that have a ^M and no carrage return (and so blend into one). There are two steps to clean this up.

1. replace all extraneous ^M:

:%s/^M$//g

BE SURE YOU MAKE the ^M USING "CTRL-V CTRL-M" NOT BY TYPING "CARROT M"! This expression will replace all the ^M's that have carriage returns after them with nothing. (The dollar ties the search to the end of a line)

2. replace all ^M's that need to have carriage returns:

:%s/^M/ /g

Once again: BE SURE YOU MAKE the ^M USING "CTRL-V CTRL-M" NOT BY TYPING "CARROT M"! This expression will replace all the ^M's that didn't have carriage returns after them with a carriage return.

Voila! Clean file. Map this to something if you do it frequently.

:help ffs - for more info on file formats

thanks to jonathan merz, douglas potts, and benji fisher

2. Using the Set Method

Ripped gratuitously from http://vim.sourceforge.net/tips/tip.php?tip_id=145
Those of us doomed to work in both the Unix and Windows world have many times encountered files that were create/editted on systems other that the one we are on at the time of our edits. We can easily correct the dreaded '^M' at the end of our Unix lines, or make files have more than one line in DOS by:

To change from <CR><LF> (DOS) to just <LF> (Unix):

:set fileformat=unix
:w

Or to change back the other way:

:set fileformat=dos
:w

It also works for Apple land:

:set fileformat=mac
:w

And to tell the difference:

set statusline=%<%f%h%m%r%=%{&ff}\ %l,%c%V\ %P

This shows what the current file's format is.