[ng12]

With TypeScript I can make a change and immediately get a list of every single line I need to update. None of those replace that very key functionality.

> and you can't leave those out safely

Who's advocating for the replacement of code review, specs, and tests with TypeScript? TypeScript makes these things better, it doesn't replace them.

[z3t4]

You can make the life of others more easy by always naming the same thing the same, eg always naming foo.bar foo.bar and you wouldn't need to annotate them, and everyone will know what it is. But if changing something means you also need to modify code at a lot of other places you have a architecture/pattern issue. Such a change should always be a semver major.