Upgrade to modern JS like es6 or es7

[nicolaskruchten]

trafficstars

I don't even know what the right name is any more, but basically modernize our codebase to enable folks who never learned ES5 to contribute :)

My main question now is: is such an upgrade so mechanical that it's zero-risk and we can just do i in a patch or minor? Or are we sufficiently worried that we should do it in the 2.0 cycle just in case it shakes something loose?

[nicolaskruchten]

We could even just start using a transpiler... we don't need to change much of our code so long as we accept the new idioms :)

[alexcjohnson]

The only concern I have about doing this in a minor is if it will break the build of someone downstream who imports plotly.js from source. If we're worried about that it could be worthwhile doing a minimal version of this in v2.0 including a transpiler and at least one change somewhere in the core that depends on transpiling.

[nicolaskruchten]

That's a thought!

[archmoj]

Addressed by #6909.