HTML::FormatText does exactly what you want. 
#!/usr/bin/perl

use strict;
use warnings;
use utf8::all;
use HTML::FormatText;
use HTML::TreeBuilder::XPath; 

my $page = q{
<div class="contents">
&#160;<ul>
<li>ChainCtrlBuildChain()
: <a class="el"   href="_chain_controller_8c.html#acb2c56087a2072b6445
+a54c17662d118">ChainController.c</a>
</li>
<li>ChainCtrlDumpChain()
: <a class="el" href="_chain_controller_8c.html#a13ed5a02bf232b115b9a5
+8cdd13dadd7">ChainController.c</a>
</li>
<li>ChainCtrlExit()
: <a class="el" href="_chain_controller_8c.html#a9e30e46ebc5411537efe9
+5a286e27cb4">ChainController.c</a>
</li>
<li>ChainCtrlGetBitStreamChan()
: <a class="el" href="_chain_controller_8c.html#a00faa6e64ea466d4ec573
+39017e57e71">ChainController.c</a>
</li>
<li>ChainCtrlInit()
: <a class="el" href="_chain_controller_8c.html#aed300a388eff2fa9c7565
+025982faab1">ChainController.c</a>
</li>
</ul>
</div><!-- contents -->
};

my $tree = HTML::TreeBuilder::XPath->new_from_content($page);

my(@trees) = $tree->findnodes('//div[@class="contents"]');
foreach $tree(@trees) {
    my $formatter = HTML::FormatText->new(
        leftmargim  => 0,
        rightmargin => 50,
    );
    print $formatter->format($tree);
}

[download]

In reply to Re: using TreeBuilder in perl by Khen1950fx
in thread using TreeBuilder in perl by anirban0328

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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