Typescript tells me property 'padStart' does not exist on type 'string'. Why? : <p>When I type in the chrome dev tools:</p>

<pre><code>"1".padStart(2,0)
</code></pre>

<p>I get </p>

<pre><code>"01"
</code></pre>

<p>But when I write </p>

<pre><code>"1".padStart(2,0)
</code></pre>

<p>in my typescript project</p>

<p>I get</p>

<pre><code>Property 'padStart' does not exist on type 'string'.
</code></pre>

<p>Why does Typescript complain? How do I fix this?</p>
