#!/usr/bin/perl -w

use strict;

while ( <DATA> ) {


        s/ angle brackets between element pairs / instead make square bracketed /


        print $_ . "\n";


}

__DATA__

<sometag> my data here </sometag>
<anothertag> further text </anothertag>
<furthertag> not good as contains <this> in angle brackets </furthertag>
<byetag> another possibility is <more> <than> one <angle pairs> in here </byetag>

##</code><code>##

<sometag> my data here </sometag>
<anothertag> further text </anothertag>
<furthertag> not good as contains [this] in angle brackets </furthertag>
<byetag> another possibility is [more] [than] one [angle pairs] in here </byetag>