&gt; That actually does allow the same name to be used as a scalar, an array and a hash, but it&#x27;s considered very bad practice.<p>Are you sure?  I could have sworn that I&#x27;d seen this as actual style advice in the Camel book.  A trip through `perldoc perlvar` (<a href="http:&#x2F;&#x2F;perldoc.perl.org&#x2F;perlvar.html" rel="nofollow">http:&#x2F;&#x2F;perldoc.perl.org&#x2F;perlvar.html</a>) shows that, at the very least, Perl itself doesn&#x27;t abide by this convention; for example, we have the scalar `$ARGV`, the list `@ARGV`, and the filehandle `ARGV`.