title: How to match a number but not a string and number together?
body: <p>I have a variable like this</p>
  
  <pre><code>p &lt;= 0;
  p &lt;= q0;
  </code></pre>
  
  <p>I want to get only the line <code>p &lt;= q0</code> but not <code>p &lt;= 0</code> so I used the code below to get the the thing except number but it cannot get the q0 also since behind q there is a  number. </p>
  
  <pre><code>if ($string2 =~ m/^(.*)(&lt;=)(.*)(;)/g) {
       unless ($3 =~ /[0-9]/) {
          push @des, $1;
          push @source, $3;
       }
  }
  </code></pre>
  
  <p>This is part of the code to match these two lines. $string 2 is first p&lt;=0 and follow by p&lt;=q0.</p>