The answers so far in this thread have all honed in on "escape key" meaning "how do I write a regex that matches this as a delimiter".

One other meaning for "escape" that I would suggest is likely as valid is "how do I write the data so that it can also include a pipe character?"

For that, we can't answer as quickly. We'll have to write both the parser and specify the data for that parser.

Anyway, I just saw it amusing that everyone went for one end of the problem when it might be the other.

-- Randal L. Schwartz, Perl hacker