<pre class="shiki github-dark shaku"><code>// your code here, please don't use InstanceType&lt;T&gt; in your codetype MyInstanceType&lt; T extends new (...args: any[]) =&gt; any&gt; = T extends new (...args: any[]) =&gt; infer R ? R : never;</code></pre>

This is my accepted solution

For a constructor function type T, InstanceType<T> returns the instance type. Please implement MyInstanceType<T> by yourself. class Foo {}type A = MyI…