A couple of times now I came accross situations where I (or someone asking me a question!) had an XML document that included a list of elements, and I wanted to process only the last one of those.

Tree-based processing is pretty lame in such a case, yes, even with XML::Twig! ;--( so here is a solution based on XML::PYX. You need to have XML::PYX intalled to run this, to get pyx and pyxw.

You can then process the output fragment as you want.

#!/bin/perl -w
use strict;

# this tool outputs the content of the last tag $tag in an xml file
# for the file file.xml:
# <doc><elt>elt 1</elt><elt>elt 2</elt><foo>elt 3</foo></doc>
# last_tag elt file.xml outputs <elt>elt 2</elt> 

my $USAGE= "$0 <tag> [file(s)]";
my $tag= shift || die $USAGE;

my $buffer;          # store the current $tag content
my $add_to_buffer=0; # 0 -> do not add to buffer, 1-> add

open( XML_IN, "pyx @ARGV | ") or die "cannot pyx input file(s): $!";

while( <XML_IN>)
  { if( m/\($tag$/) { $add_to_buffer= 1; $buffer= ''; }  # get start t
+ag
    $buffer.= $_    if( $add_to_buffer);                 # fill buffer
    if( m/\)$tag$/) { $add_to_buffer= 0;              }  # get end tag
  }

close XML_IN;

open( XML_OUT, "| pyxw") or die "cannot output buffer: $!";
print XML_OUT $buffer;
close XML_OUT;

# I need this to output the last line on my linux box with Perl 5.6.1
print "\n";

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In reply to Output the content of the last element with a given tag in an XML file by mirod

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