I develop a library that needs to load async in pages. My script load:

```
<script type="text/javascript">
  (function(w,d) {
    var po = d.createElement('script'); po.type = 'text/javascript'; po.async = true;
    po.src = 'my_function-sdk.js';
    var s = d.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s);
  })(window, document);
</script>

```

I want to use the function immediately below:

```
<script>
      my_function("test");
</script>

```

Or in a click:

```
<a href="#" onclick="my_function('other test');">test click</a>

```

The function definition in file `my_function-sdk.js`:

```
function my_function(param) {
  console.log("in correct function");
  console.log(param);
}

```

I want that console.log print *"in correct function"* how was defined in my function on file `my_function-sdk.js`.

JSFiddle: <https://jsfiddle.net/adrianogodoy/n7ahygoj/8/>

EDIT: 
I want to do like Google Analytics, using `ga` function immediately bellow the load script or any other place without receive a *not defined* error:

```
  <script>
    (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
    (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
     m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
    })(window,document,'script','//www.google-analytics.com/analytics.js','ga');

    ga('create', 'UA-XXXXXXX-1', 'auto');
    ga('send', 'pageview');
</script>

```