ES Discuss - Message History

Brendan Eich (2013-08-31T19:52:36.000Z)

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> Yuichi Nishiwaki <mailto:yuichi.nishiwaki at gmail.com>
> August 31, 2013 12:45 PM
> ES5 specifies "yield" as a reserved keyword, right?

Wrong, only ES5 strict reserved "yield".

> So there should be
> no need to make it contextual.
>
There is; when we first tried reserving "yield" in 2006, we had to put 
it behind opt-in versioning because content used "yield" as an 
unqualified identifier. IIRC it's still used.

Backward compatibility is what it is. "use strict"; in ES5 was an 
opt-in, so not widely adopted enough (i.e., universally adopted) to help.

/be

domenic at domenicdenicola.com (2013-09-08T00:53:14.628Z)

 Yuichi Nishiwaki <mailto:yuichi.nishiwaki at gmail.com> August 31, 2013 12:45 PM
> ES5 specifies `yield` as a reserved keyword, right?

Wrong, only ES5 strict reserved `yield`.

> So there should be no need to make it contextual.

There is; when we first tried reserving `yield` in 2006, we had to put 
it behind opt-in versioning because content used `yield` as an 
unqualified identifier. IIRC it's still used.

Backward compatibility is what it is. `"use strict";` in ES5 was an 
opt-in, so not widely adopted enough (i.e., universally adopted) to help.

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