title: Writing multiple logical operators more concisely
body: <p>I'm trying to write multiple logical operators in a more concise way. In my case, I want the function to only run when all four inputs are only numbers. The only way I can think of doing this is to write them all in one if statement with &amp;&amp;, use multiple ifs (as below), or use switch. But I was wondering if there is a more concise way.</p>
  
  <pre><code>    function fn() {
  
      const input = display.getInput();
  
      if (input.p !== "" &amp;&amp; !isNaN(input.p)) {
  
          if (input.d !== "" &amp;&amp; !isNaN(input.d)) {
  
              if (input.s !== "" &amp;&amp; !isNaN(input.s)) {
  
                  if (input.y !== "" &amp;&amp; !isNaN(input.y)) {
  
                      if (input.y &lt;= 100) {
  
                          /* run code */
                      } 
                  }
              }
          } 
      }    
  }
  </code></pre>