As said before, don't use regexp, use a module.

But much to the surprise of everyone here, I am not going to pimp XML::Twig this time! xml_grep2, packaged as App::xml_grep2, will do this quite simply from the command line:

xml_grep2 -v '//start_element[.//user_id]' user.xml > elements_with_no
+_user_id.xml
xml_grep2 -v '//start_element[count(.//user_id)=0]' user.xml > element
+s_with_user_id.xml

[download]

xml_grep2 works like grep, except it uses XPath instead of regular expression. So the -v flag will filter out any element that matches the XPath expression. The first one matches elements with a user_id descendant, and the second one matches elements with none.

Voilą!

In reply to Re: Need to process a XML file through Perl by mirod
in thread Need to process a XML file through Perl by paragkalra

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