Question

Using a Perl replace statement (s//) I’d like to modify some XML by adding an attribute to some items if missing. Here’s an example :

...
<car color="red" owner="john">...</car>
<car color="green" age="3">...</car>
...

Let’s say I’d like to add a default owner to ownlerless cars. I tried the following without success :

s/(<car[^>]*)(?!owner="[^"]*")(.*>)|$1 owner="steve"$2/iUg

Any help appreciated.

Answer 1

While you may be able to get away with a regex, an XML parser is always recommended.

Perl/CPAN offerings include:

• XML::Simple

  Treats your XML document like a Perl data structure

• XML::Parser

  An old-timer

• XML::SAX

  For SAX parsing needs

• XML::Twig

  For memory-efficient processing of XML documents in chunks

• XML::LibXML

  My personal favorite