Vim regex to substitute/escape pipe characters

Question

Let\'s suppose I have a line:

a|b|c

I\'d like to run a regex to convert it to:

a\\|b\\|c

In most regex engine

Answer 1

Vim does the opposite of PCRE in this regard: | is a literal pipe character, with \| serving as the alternation operator. I couldn't find an appropriate escape sequence because the pipe character does not need to be escaped.

The following command works for the line in my example:

:. s%|%\\|%g