I guess sharing a stack would help... 
# this code is missing a lot. don't expect it to work :)
{
 my @stack;
 sub start {
  push @stack, $tag;
 }
 sub end {
  if ($tag eq 'cfif' and $stack[-1] eq 'cfelse'){
   pop @stack;
  }
  die "Invalid code" if pop(@stack) ne $tag;
 }
 sub text {
  # use @stack to determine where we are...
 }
}
my $parser = HTML::Parser->new(start_h => [\&start, 'tagname'],
                               end_h   => [\&end,   'tagname'],
                               text    => [\&text,  'text'],
);
$parser->report_tags(qw/cfif cfelse cfend/);
$parser->parse($cfml);

[download]
---
<body><cfif>foo<cfelse><b>bar</b></cfif></body>
==>  text  '<body>';
     start 'cfif';
     text  'foo';
     start 'cfelse';
     text  '<b>bar</b>';
     end   'cfif';

[download]

2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$

[download]

In reply to Re: Re{4): Template Parsing - Finding tag pairs. by Juerd
in thread Template Parsing - Finding tag pairs. by vladb

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