Could you add intellisense feature for C++/JS code? It’d be really useful if it could autocomplete both standard JS functions and those that belong to GD/Pixi or even XDK Api. And it would be in line with what GD stands for - easy game creation, any way you want.
Autocompletion is really something complicated, most text editor and even IDE don’t do it well because it’s quite complicated to analyze the code being typed. (The most advanced auto completion can be seen in Eclipse/NetBeans and Java IDE because Java has a good support for reflection. For C++, Visual Studio has a good support but of course it can’t be of any help here. For Javascript, WebStorm does some kind of autocompletion.)
If you really use intensively JS events, the best thing to do in my view would be to write the code in separate files, so you can use an editor (Sublime Text/Atom/WebStorm) that has plugin or builtin support for autocompletion and benefit from the editor advantages (multiselection in Sublime Text for example which is just awesome).