title: Merging/ Extending Typescript React-Native interfaces
body: <p>So I've a little dilema here, I'm using react native together with Typescript. </p>
  
  <p>Have @types/react-native installed which has an interface 'TextInputStatic' declared under node modules @types/react-native.</p>
  
  <pre><code>export interface TextInputStatic extends NativeMethodsMixin, TimerMixin, React.ComponentClass&lt;TextInputProperties&gt; {
      State: TextInputState;
  
      /**
       * Returns if the input is currently focused.
       */
      isFocused: () =&gt; boolean;
  
      /**
       * Removes all text from the input.
       */
      clear: () =&gt; void;
  }
  </code></pre>
  
  <p>In my component I need to use custom props for TextInput but because of interfaces defined in node modules typescript compiler throws an error:</p>
  
  <pre><code>Type '{ prop1: { name: string; anonymous: boolean; }; prop2: "f"; }' has no properties in common with type 'IntrinsicAttributes &amp; IntrinsicClassAttributes&lt;Component&lt;TextInputProperties, ComponentState, nev...'.
  </code></pre>
  
  <p>When used like this:</p>
  
  <pre><code>&lt;TextInput prop1={{name: 'loginField', anonymous: false }} prop2='f'&gt;&lt;/TextInput&gt;
  </code></pre>
  
  <p>I looked at merging/ extending interfaces but no luck so far. Anyone knows how can I extend or allow TextInput to have custom props?</p>
  
  <p>What I've tried to do is created an index.d.ts file and then:</p>
  
  <pre><code>import * as Native from 'react-native';
  
  interface InputType extends Native.TextInputStatic{
      prop1?: any;
  }
  </code></pre>
  
  <p>But no luck</p>
  
  <p>Thanks</p>