&gt; implicit conversion of numeric strings to numbers in certain contexts.<p>In Perl 6 at least, and to a large degree Perl 5 too, context only &quot;causes&quot; bugs if coders make assumptions that are invalid in Perl.<p>For example:<p><pre><code>  say $foo + $bar
</code></pre>
adds two numbers. So the context for $foo and $bar is numeric. So Perl coerces them to be numbers. If you didn&#x27;t mean to add two numbers, don&#x27;t use a numeric operation such as `+`.<p>If you want Perl 6 to make sure $foo and $bar are numbers already, then add a type to their declaration:<p><pre><code>  my Int ($foo, $bar);</code></pre>