title: Element implicitly has an 'any' type because type '{}' has no index signature. [7017]
body: <p>I am using typescript and am seeing the following error</p>
  
  <blockquote>
    <p>[ts] Element implicitly has an 'any' type because type '{}' has no index signature. [7017]</p>
  </blockquote>
  
  <pre><code>const store = {};
  setItem: jest.fn((key, value) =&gt; {
      store[key] = value.toString();
  })
  </code></pre>
  
  <p>I can fix it by setting the store to any like so</p>
  
  <pre><code>const store: any = {};
  </code></pre>
  
  <p>but I would like to type it, but can't figure out how to do this. Can anyone help?</p>