I agree with Brendan about the difficulty of mapping features from AS3 (Flash) to ES4 (the web). I'd go a step further and say that the only way this even would have been possible is to grow it out of the host's DNA of JS1/ES3.
Even if at a high level many of the emerging features of JS look like those in AS3/ES4, they are in their details profoundly different. This is as it should be. They need to grow out of the primordial stuff of JS1, not AS3. I suspect that the ES4 effort has informed many of those now working on ES.next in a way that wouldn't have happened otherwise. So in that sense, at least, ES4 lives on.
I agree with Brendan about the difficulty of mapping features from AS3 (Flash) to ES4 (the web). I'd go a step further and say that the only way this even would have been possible is to grow it out of the host's DNA of JS1/ES3.
Even if at a high level many of the emerging features of JS look like those in AS3/ES4, they are in their details profoundly different. This is as it should be. They need to grow out of the primordial stuff of JS1, not AS3. I suspect that the ES4 effort has informed many of those now working on ES.next in a way that wouldn't have happened otherwise. So in that sense, at least, ES4 lives on.