title: This expression is not callable Type 'String' has no call signatures
body: <p>In my Typescript Function, when I set the type annotation to String, I receive the error "This expression is not callable Type 'String' has no call signatures." as seen in the code below.</p>
  
  <pre><code>function thing&lt;T&gt;(setThingState: string ){
  
      return Axios.request({
          method: 'get',
          url:'https://jsonplaceholder.typicode.com/todos/',//'https://jsonplaceholder.typicode.com/todos/'
      }).subscribe(
          response =&gt; {
              console.log(response);
              setThingState({ message: response.status });
          },
          error =&gt; {
              console.log(error);
              setThingState({ message: '404' });
          }
      );
  
  }
  </code></pre>
  
  <p>However, if I set the type to Any, then I have no issues. As seen in the code below. I'm still wrapping my head around TypeScript, so any feedback would be appreciated.</p>
  
  <pre><code>function thing&lt;T&gt;(setThingState: any ){
  
      return Axios.request({
          method: 'get',
          url:'https://jsonplaceholder.typicode.com/todos/',//'https://jsonplaceholder.typicode.com/todos/'
      }).subscribe(
          response =&gt; {
              console.log(response);
              setThingState({ message: response.status });
          },
          error =&gt; {
              console.log(error);
              setThingState({ message: '404' });
          }
      );
  
  }
  </code></pre>
  
  <p>This Function is then being called in a React Functional Component, with Redux as seen in the following: </p>
  
  <pre><code>const [thingState, setThingState] = useState({ message: ''});
      function testCall(){
          thing(setThingState);
      };
  </code></pre>