Re: A data structure for XML generation

[grantm]

not easy/possible to specify when something is an attribute versus an element using XML::Simple

Actually XML::Simple has a very simple rule for determining whether to output something as an attribute vs a nested element. If the value is a plain scalar, it will be output as an element, otherwise it will be a nested element. E.g.:

print XMLout({person => { id => 123, name => ['John Doe']}})

gives:

<opt>
  <person id="123">
    <name>John Doe</name>
  </person>
</opt>

Having said that, I'd encourage the use of a different module for anything non-trivial.

[metaperl]

Actually XML::Simple has a very simple rule for determining whether to output something as an attribute vs a nested element. If the value is a plain scalar, it will be output as an element, otherwise it will be a nested element.

Indeed... Just FYI, a co-worker and myself were evaluating XML::Simple for producing XML and he had the impression that there was no way to do this. If you glance at the SYNOPSIS, and see this:

'gobi'          => {
              'osversion'     => '6.5',
              'osname'        => 'irix',
              'address'       => '10.0.0.102'
          },

you get the idea that there is no way to force address to be an element somehow.

I knew about ForceArray but for some reason, things didn't click for me until your post here.

regexps as "non-plain scalars"

I wanted to ease my typing. The standard "non-plain scalar" is this:

mother => ['Mary']

but I was hoping to get away with this:

mother => qr/Mary/

because it is easier to type and more readable (IMHO).

Any chance of converting a node whose value is a regexp into an element as opposed to an attribute?

Order of sibling XML elements

Now, one other question, we are producing XML based on an XSD. I am wondering if the XML has order requirements on siblings. In other words, I did the sample XML for the original topic in this thread in XML::Simple -

use strict;
use warnings;

use XML::Simple;
use Tie::IxHash;


tie (my %struct, 'Tie::IxHash',

 family => { 
        name => 'Kawasaki', 
        father => ['Yasuhisa'],
        mother => ['Chizuko'],
        children => {
             girl => ['Shiori'],
             boy  => ['Kairi'],
            }
       }
);          
         
warn XMLout(\%struct);

but while each level of the XML tree was accurate, the sibling elements father, mother, children were in a different order than I wanted them to be.

[grantm]

The short answer is that XML::Simple is absolutely not the right module for generating XML. I don't generate XML very often and when I do I tend to use a templating tool like TT or Mason.