Use typescript

[cibernox]

The more I use VSCode the more I value the little helps that the type definitions (even those defined externally like momentjs / lodash).

Although Ember's flexibility limit the effectiveness of types, this barely relies in Ember. Many of the arguments and return types (e.g NodeList) can be known in advance.

It is possible to develop addons in typescript already? Shall we?

[rwjblue]

Yes, we can. Seems fine to start experimenting.

The basic tldr; is that we need to add ember-cli-typescript to the repo, and start converting.

[pixelhandler]

Per @robbiepitts ... FWIW, this is a good resource for TS compilation: https://github.com/glimmerjs/glimmer-build/blob/master/index.js

[pixelhandler]

@danielchappell let me know if you have any ideas on getting TS to work in an addon.