I have code like this

```
var e = new window[className](...);

```

where 

```
className

```

is a name of some "class" I've created and is specified in an attribute in my html.
All I had to do was make sure I had loaded a constructor/function of the name in className and it worked. 

I've started getting all my stuff into *require* and this has unsurprisingly stopped working. 
I have a file Eric.js which I have required, and contains

```
define('Eric',function(){
var Eric = function (ED) {
...
};
// etc

return Eric;
});

```

but

```
require(['wtt/Eric']);
className='Eric';
var e = new window[className](...);

```

produces

```
TypeError: window[className] is not a constructor

```