Let's say that tomorrow, Microsoft releases a totally-backwards-incompatible build of Typescript, and starts charging for it.

My "way out" of the Typescript ecosystem is:

1.) Change the target to "ES6", and run a compile. 2.) Take those files and use them as my new source files. 3.) Remove Typescript from my build pipeline.

Done. Easiest language migration I've ever done.

Its interesting that on one hand, we have this shouting "embrace, extend, extinguish!" directed at TypeScript, and on the other, Facebook with Flow and Babel is doing precisely that: its extending JS with their own type system, adding support for said type annotations to Babel (which is still thought of as the es.next -> es.current compiler) and still calling it JavaScript; or at least, muddying the waters (no extension change).

Strangely, it appears to work. I've seen claims that Flow is better because "its just JavaScript, not another language"

I don't get it.

Considering it is open source, this would be the death of the project for them. Someone would fork it and keep it at a specific version, maybe with community additions. Existing projects could just keep on using it at that version, or move on to ES6 equivalents with little change.

I would shed no tears if JS were extinguished. It's a terrible mongrel language that is not well suited for large projects. TS is a tremendous improvement, if you ask me.

Under what mechanism would the "extinguish" part be at all possible?

When using TypeScript subtly forces you into a MS toolchain.

Then when everyone's hooked on VS Code BAM VS Code Pro Extreme Edition!

Strangely enough, I'd feel this would be fine. I would pay for a non-free upgrade of VSCode if it really brings in enough value. Its already on par with Sublime, and I paid for that...

edit: Though if you mean TypeScript depending on VSCode to build, I doubt thats even possible at this point. Everything is available via the command line. Heck, there are even tools that build on top of the compiler API. (dts-generator, tslint etc)

Well not that it won't compile without VS, but maybe as a vehicle to for the occasional new feature that just doesn't work quite right on Mac, one drive hosted git tie in's, I dunno but their up to something.

Considering VS Code is a light, free alternative to Visual Studio, that scenario is positively absurd.

No, that's not how that works.

EEE refers to the times when Microsoft would take an open standard--say HTML, or JavaScript, back when IE3 was actually the best browser on the market--shove in their own, proprietary, backwards-incompatible extensions, and keep calling it the same thing as the open standard.

But MS makes it very clear that TypeScript is a different language. It helps a lot that they don't even have the same name, y'know. Also, it's a system for specifically staying backwards compatible with open-standard JavaScript. Using TypeScript does not replace JavaScript. It supplements it.