Use some-kind of type validator

[stereobooster]

For example puppeteer uses TypeScript to validate code based on jsdoc annotations puppeteer/puppeteer#986

Also flow can do some validation, but not sure if there is puppeteer type definitions.

[peterbe]

Are you suggesting that we rewrite it in TypeScript? I wouldn't mind.

[peterbe]

Worth thinking about the fact the minimalcss isn't much of a lib. It's just an elaborate script around something much more powerful.

[stereobooster]

We can use TypeScript for checking types in JS files.

Worth thinking about the fact the minimalcss isn't much of a lib

Exactly. It is very hard to write unit tests, only integration tests make sense. But with type checker we can verify that we avoid some class of errors without huge test cases.

[peterbe]

Sure. I'm up for it. I've never actually used TypeScript and I'm eager to try it. Will you lead the way?