use strict;
my $str = 'https://example2.com/file/casdqwe/test1.rar
https://example2.com/file/casdqwe/test2.rar
https://example5.com/file/casdqwe/test3.rar
http://example2.com/file/casdqwe/test4.rar
http://www.example2.com/file/casdqwe/test5.rar
http://www.example5.com/file/casdqwe/test6.rar';
my $regex = qr/\bhttps?:\/\/.*\//mp;
my $subst = '';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html