#!/usr/bin/perl -Twl
use strict;
{
    local undef $/;
    my $string = <DATA>;
    # extract strings from 'usual' quotes:
    print 'MATCH: ', $2 while $string =~ /\bq([^\w{([])(.+?[^\\])\1/sg;
    # extract strings from 'bracketted' quotes:
    for (( [ qw'{ }' ], [ qw'[ ]'], [ qw'( )' ] )) {    
        print 'MATCH: ', $1
            while $string =~ /\bq\Q$_->[0]\E(.+?[^\\])\Q$_->[1]\E/sg;
    }

}
__DATA__
my $km = q'BEGIN simple foo bar baz END';
my $kv = q#BEGIN foo bar \# baz END#;
my $kk  = q{BEGIN super foo bar          
              banzai END};  
my $kt  = q{BEGIN super foo \{super\} bar
              banzai END};