Changing regex delimiters

Pattern matching and substitution with regular expressions is a commonly used Vim feature. We’ve written a lot about substitution and pattern matching in the past.

Typically, when performing a substitution, you would use the :s command followed by a regular expression that’s delimited by slashes / and followed by any flags, such as g to replace all occurrences on the line. For example:

:s/foo/bar/g

But did you know that the regular expression delimiter can be anything and is not limited to /? This command is equivalent:

:s#foo#bar#g

Whatever character you use after the s is considered the delimiter. You can use almost any character except \, ", or |. Why would you care to use a different delimiter? Because then you don’t need to escape the slash.. For example, replacing a file path: Instead of:

:/\/User\/local\/bin\//\/usr\/sbin\//g

You can use # as your delimiter and skip escaping the / which makes for something far easier to parse:

:#/User/local/bin/#/usr/sbin/#g