Fortunately, Emacs offers help here too. Code built into Emacs implements a simple-to-use front end for SCCS, RCS, CVS, or Subversion. The single command Ctl-x v v tries to deduce the next logical version-control operation to do on the file you are visiting. The operations this includes are registering a file, checking out and locking it, and checking it back in (accepting a change comment in a pop-up buffer).^[139]

Emacs also helps you view the change history of version-controlled files, and helps you back out changes you don't want. It makes it easy to apply version-control operations to whole sets or project directory trees of files. In general, it does a pretty good job of making version-control operations painless.

The implications of these features are larger than you might guess before you've gotten used to it. You'll find, once you get used to fast and easy version control, that it's extremely liberating. Because you know you can always revert to a known-good state, you'll find you feel more free to develop in a fluid and exploratory way, trying lots of changes out to see their effects.