perl - Regex matching multiple negative lookahead

Question

I'm trying to match a string (using a Perl regex) only if it doesn't start with "abc:" or "defg:", but I can't seem to find out how. I've tried something like

^(?:(?!abc:)|(?!defg:))

Answer 1

Lookahead (?=foo), (?!foo) and lookbehind (?<=foo), (?<!foo) do not consume any characters.

You can do multiple assertions:

^(?!abc:)(?!defg:)

or:

^(?!defg:)(?!abc:)

...and the order does not make a difference.