I think this may be close to what you are asking, and only uses a module shipped in core, Text::Balanced: 

$ perl -MData::Dumper -MText::Balanced -le '
use 5.010;
$Data::Dumper::Deepcopy = $Data::Dumper::Sortkeys = 1; 
my $c = q{This is outside (This is inside).}; 
my %found; 
( $found{prefix}, $found{bracketed}, $found{postfix}, ) 
        = Text::Balanced::extract_multiple($c, 
                [ \&Text::Balanced::extract_bracketed, ], ); 
say Data::Dumper->Dump( [ \%found, ], [ qw( *f ) ] );
'
%f = (
       'bracketed' => '(This is inside)',
       'postfix' => '.',
       'prefix' => 'This is outside '
     );

[download]

Hope that helps.

In reply to Re: Regex for outside of brackets by atcroft
in thread Regex for outside of brackets by theravadamonk

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