Contexts implement the idea of cancellation along with go routine local storage and at that they work very well.

What if for the hypothetical Go 2 we add an implicit context for each goroutine. You'd probably need to call a builtin, say `getctx()` to get it.

The context would be inherited by all go routines automatically. If you wanted to change the context then you'd use another builtin `setctx()` say.

This would have the usefulness of the current context without having to pass it down the call chain everwhere.

The cognitive load is two bultins getctx() and setctx(). It would probably be quite easy to implement too - just stuff a context.Context in the G.