Installed the module... It actually produces <element/> for empty elements: 

use XML::Smart qw( );
my $xml = XML::Smart->new();
$xml->{foo}{bar}{empty} = {};
print scalar $xml->data();

[download]
<?xml version="1.0" encoding="iso-8859-1" ?>
<?meta name="GENERATOR" content="XML::Smart/1.6.8 Perl/5.008008 [MSWin
+32]" ?>
<foo>
  <bar>
    <empty/>
  </bar>
</foo>

[download]

If you use a DTD, then you need to specify the "EMPTY" keyword or else it'll generate <empty></empty> (which is fine cause it means the same thing). 

use XML::Smart qw( );
my $xml = XML::Smart->new();
$xml->{foo}{bar}{empty} = {};
$xml->apply_dtd(<<'__EOI__');
<!DOCTYPE foo [
<!ELEMENT foo (bar*)>
<!ELEMENT bar (empty*)>
<!ELEMENT empty EMPTY>
]>
__EOI__
print scalar $xml->data();

[download]

In reply to Re^2: empty element with xml::smart by ikegami
in thread empty element with xml::smart by makrospex

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.