my $vars = {
    header => 'hello, [% name %]',
    footer => 'goodbye, [% name %]',
    name => 'Dave',
}

my $template = <<"END";
[% header %]
I'm afraid I can't do that
[% footer %]
END

my $TT = Template->new();
my $output;
$TT->process(\$template,$vars,\$output) || die $TT->error();

##</code><code>##

$TT->process(\$template,$vars,\$output) || die $TT->error();
$TT->process(\$output,$vars,\$output) || die $TT->error();