Skip type check on unused parameters
<p>When I compile my typescript project, I'm using the <code>noImplicitAny</code> option so that I won't forget to specify the types on my variables and arguments.</p>

<p>However sometimes you have arguments that you don't use. For example:</p>

<pre><code>jQuery.ajaxTransport("+*", function (options: JQueryAjaxSettings) {
  return {
    abort: function (_, callback: JQueryCallback) { 
</code></pre>

<p>I am not interested in the first argument of the abort function, so I ignore it by naming it _.</p>

<p>Is that the proper way to do that in TypeScript? I couldn't find it in the guide. I suspect that it isn't the proper way, because I can only name one argument _.</p>

<p>Typescript raises the following error:  </p>

<blockquote>
  <p>error TS7006: Parameter '_' implicitly has an 'any' type.</p>
</blockquote>

<p>I could just type <code>_:any</code> but that seems a bit overkill for an argument that I don't use.</p>