laptop:~> perl -l -w -MURI
my $u = new URI();
$u->query_form('foo'=>'bar','foo'=>'baz');
print join ':', $u->query_form;
__END__
foo:bar:foo:baz

##</code><code>##

laptop:~> perl -l -w -MURI -MURI::QueryParam
my $u = new URI('http://perl.com/?a=b&foo=baz&c=d&foo=bar');
print join ', ', $u->query_param('foo');
__END__
baz, bar