Um, no. 

$s = '1 <% xxx%%> 2 <%%> 3 <%>%> 4 <% >% %> 5 <%%%% xxx %%%%> 6 ';

$s =~ s/<% (?> [^%]+ | %+ [^>]+ )* %>/!REPLACED!/xg; 
print $s;

1 !REPLACED!%> 4 <% >% %> 5 <%%%% xxx %%%%> 6

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In reply to Re: Re^4: A NOT in regular expressions (why [^%>]?) by BrowserUk
in thread A NOT in regular expressions by Anonymous Monk

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