in reply to %% in perl mean

In this case, it's just two percent character which are being searched for in a search-and-replace operation (s///). However it does have two special meanings in Perl...

  1. The printf and sprintf functions take a formatting string as their first argument. This formatting string uses special codes that start with a "%" character; such as "%d" which is a placeholder for an integer. When you want the output to include a literal "%" character, you can't just place that as-is in the formatting string; instead you use "%%".

  2. The other place "%%" is special in Perl is that there's a global hash called %%. You can assign values to it and use it like any other hash; the only difference is that you don't declare it with my or our - it's pre-defined.

    use Data::Dumper; %% = (foo => 1, bar => 2); print Dumper \%%;
use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name