It wasn't an accident in Typescript. Each step along the way seemed well deliberated and to facilitate reasoning about someone's code, despite the computational

It wasn't an accident in Typescript. Each step along the way seemed well deliberated and to facilitate reasoning about someone's code, despite the computational complexity trade-offs. (That a lot of that was to facilitate reasoning about nearly untyped JS code doing a lot of dynamic code things is, depending on which side of the deliberation you are on: 1] a sign that dynamic code has always been that complex and developers have had to do all that sort of "compile time logic" in their own heads for so long, and/or 2] a sign that Typescript's "flaws" come from trying to be too supportive of existing bad JS code.)