Abigail-II and dws have valid points you should take to heart, but don't answer your original question which is about the difference between or and ||. The difference is in precedence, || has higher precedence than or. This can be found in the perlop manpage.

Note: especially keep in mind the relative precende of or and || with respect to assignment.

Just my 2 cents, -gjb-

In reply to Re: To || or not to or and why. by gjb
in thread To || or not to or and why. by krisahoch

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