Practical Vim, 2nd Edition

Tip 94

Rearrange CSV Fields Using Submatches

In this tip, we’ll see how submatches captured from the search pattern can be referenced in the replacement field.

Let’s say that we have a CSV file containing a list of email addresses along with first and last names:

substitution/subscribers.csv

last name,first name,email
neil,drew,[e-mail]
doe,john,[e-mail]

Now suppose that we want to swap the order of the fields so that the email comes first, then the first name, and finally the last name. We could use this substitute command to do it:

/\v^([^,]*),([^,]*),([^,]*)$
:%s//\3,\2,\1

In the pattern, [^,] matches anything that isn’t a comma. So ([^,]*) matches zero or more consecutive non-commas and captures the result ...