title: Perl Variable value is representing another variable
body: <pre><code>my $var = "Hello";
  my $Hello = "Hi";
  </code></pre>
  
  <p>my question is: how can I substitute the value of $Hello in $var?
  Here $var contains string "Hello" (there is a variable with same name $Hello). I am looking for a way to substitute it with the value of variable $Hello. 
  Please let me know how can I do that?</p>