The normal answer would be use HTML::TokeParser if you want a reliable solution to parse HTML. For this *particular* task a well constructed regex should suffice. This will strip all the <b> </b> tags that are empty. I believe it covers all bases. 

$text = join '', <DATA>;
print $text;
$text =~ s#<\s*b\s*>(?:[\s\n]|&nbsp;)*<\s*/\s*b\s*>##ig;
print $text;

__DATA__
<p>test
<p>test<b></b>
<p>test<b
>&nbsp;  
</b>
<p>test<b>  </b>
<p>test<b 
></b >
<p>test<B></B>
<p>test<B>

</B>
<p>test<B ></B>
<p>test<B
>  </B >
<p>test<B>  &nbsp;  &nbsp; </B>
<p><b>I am not empty!</b>

[download]

In reply to Re: how-to strip empty HTML tags like b /b by tachyon
in thread how-to strip empty HTML tags like &lt;b&gt; &lt;/b&gt; by russmann

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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