title: Argument of type 'X' is not assignable to parameter of type 'X'
body: <p>Good day. I'm new to Type Script, using VSCode.</p>
  
  <p>Getting following errors:</p>
  
  <ol>
  <li><blockquote>
    <p>error TS2322: Type '() => string' is not assignable to type 'string'.</p>
  </blockquote></li>
  <li><blockquote>
    <p>error TS2322: Type '() => number' is not assignable to type 'number'.</p>
  </blockquote></li>
  </ol>
  
  <p>The Code: </p>
  
  <p><strong>DTO.ts</strong></p>
  
  <pre><code>interface DTO {
  
      getId(): number;
      getValue(): string;
  }
  export = DTO;
  </code></pre>
  
  <p><strong>LinkedObject.ts</strong></p>
  
  <pre><code>class LinkedObject {
  
      public value: string = "Not Set";
      public id: number = 0;
  
      constructor(value?: string, id?: number) {
          this.value = value;
          this.id = id;
      }
  }
  export = LinkedObject;
  </code></pre>
  
  <p>I am trying to instantiate <code>LinkedObject</code> class using above mentioned interface methods: </p>
  
  <p><strong>TravelClientFormPopulator.ts</strong></p>
  
  <pre><code>class TravelClientFormPopulator {
  
      public populateComboBoxUsingDTOs(dataObjects: Array&lt;DTO&gt;, comboBoxID: string): void {
  
          // Get the combo box
          var selectElement = &lt;HTMLSelectElement&gt; document.getElementById(comboBoxID);
          // Reset the options 
          selectElement.options.length = 0;
  
          var linkedObjectsToAdd: LinkedObject[] = new Array&lt;LinkedObject&gt;();
  
          var defaultLinkedObject: LinkedObject = new LinkedObject("Not Selected", 0);
  
          linkedObjectsToAdd.push(defaultLinkedObject);
  
          for (var i = 0; i &lt; dataObjects.length; i++) {
              var value: string = dataObjects[i].getValue; // Error here
              var id: number = dataObjects[i].getId; // And here
              var linkedObject: LinkedObject = new LinkedObject(value, id);
          }
      }
  }
  </code></pre>
  
  <p>Any help will be highly appreciated. </p>