#! perl -slw
use strict;

my %lookup;
@lookup{map chr, 32..127}=map chr, 32..127;
@lookup{'{', '(',  '[', '<'} = ('}', ')', ']', '>');

my $string = do{ local $/; <DATA>};
print "Match:'$2'" while $string =~ m[\bq(.)(.+?(??{ $lookup{$1} }))]sog;

__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};