http://www.perlmonks.org?node_id=975660

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I have XML in the form:

<a:houses>
    <a:house>
        <a:sq_footage/>
        <a:address/>
    </a:house>
    <a:house>
        <a:sq_footage/>
        <a:address/>
    </a:house>
</a:houses>

[download]

I need to strip off the namespace a. The XML::Twig CPAN page talks of mapping namespaces, but I am unclear as to whether this will solve my problem here.

Any insight shared would be appreciated. Thanks!

Replies are listed 'Best First'.
Re: removing namespaces with XML::Twig?
by ikegami (Patriarch) on Jun 11, 2012 at 23:38 UTC

    "a" is not a namespace, it's a prefix.

    Are you trying to strip the prefix without changing the element's namespace so 

    <a:houses xmlns:a="...">
   <a:house>
      ...
   </a:house>
   ...
</a:houses>

    [download]

    becomes 

    <houses xmlns="...">
   <house>
      ...
   </house>
   ...
</houses>

    [download]

    Or are you trying to change the namespace of the element to nothing and thus stripping the prefix so 

    <a:houses xmlns:a="...">
   <a:house>
      ...
   </a:house>
   ...
</a:houses>

    [download]

    becomes 

    <houses>
   <house>
      ...
   </house>
   ...
</houses>

    [download]

    (Either way, can't help you.)

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      Thanks for the correction. I'm wanting to strip off the prefix.
[reply]
        The prefix gets stripped off in both versions, so that doesn't answer anything.
[reply]
Re: removing namespaces with XML::Twig?
by mirod (Canon) on Jun 12, 2012 at 07:08 UTC

    As mentioned above, you need to set each tag to a non-prefixed version of itself.

    _all_ triggers a handler on each tag, tag gives you the tag name and set_tag sets it:

    #!/usr/bin/perl

use strict;
use warnings;

use XML::Twig;

XML::Twig->new( start_tag_handlers => { _all_ => sub { my $tag= $_->ta
+g; $tag=~ s{^[^:]*:}{}; $_->set_tag( $tag); } },
                                       keep_spaces => 1, # to keep for
+mating
              )
         ->parse( \*DATA)
         ->print;

__DATA__
<a:houses>
    <a:house>
        <a:sq_footage/>
        <a:address/>
    </a:house>
    <a:house>
        <a:sq_footage/>
        <a:address/>
    </a:house>
</a:houses>

    [download]
[reply]
[d/l]
Re: removing namespaces with XML::Twig?
by bitingduck (Chaplain) on Jun 12, 2012 at 03:45 UTC

    I tried the obvious of taking the example for "map_xmlns" and seeing if I could substitute an empty prefix. The result was that it leaves the prefix unchanged:

    #!/usr/bin/perl
#very slightly modified example lifted from the docs

use strict;
use warnings;
use XML::Twig;



my $t= XML::Twig->new( map_xmlns => {'http://www.w3.org/2000/svg' => "
+"},
                         twig_handlers => 
                           { 'svg:circle' => sub { $_->set_att( r => 2
+0) } },
                         pretty_print => 'indented', 
                       )
                  ->parse( '<doc xmlns:gr="http://www.w3.org/2000/svg"
+>
                              <gr:circle cx="10" cy="90" r="10"/>
                           </doc>'
                         )
                  ->print;

    [download]

    The output is:

    <doc xmlns:gr="http://www.w3.org/2000/svg">
  <gr:circle cx="10" cy="90" r="10"/>
</doc>

    [download]

    If I put the "svg"in the example back in the hash, it works as in the example. If I put a space, I get a prefix that's a space and a colon. XML::LibXML::Element will let you turn off the namespace prefix element by element, but I'm too lazy right now to work through that one. Try poking around through the various XML::LibXML children.

[reply]
[d/l]
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Re: removing namespaces with XML::Twig?
by Anonymous Monk on Jun 12, 2012 at 01:56 UTC
[reply]

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