More fun with undefined
Tab Atkins Jr.
jackalmage at gmail.com
Thu Jun 14 15:41:17 PDT 2012
On Thu, Jun 14, 2012 at 3:29 PM, Allen Wirfs-Brock
<allen at wirfs-brock.com> wrote:
> This is a different issue, but I wonder how badly the web would break if we
> made undefined a reserved word. Does anybody in JS really declare a
> different local binding for undefined? In ES5 we got away with making
> undefined read-only. Maybe we should continue pushing and see if we can
> eliminate the rebindable undefined hazard.
There are definitely plenty of scripts on the web that *declare*
undefined to shorten the scope look-up, either by using "var
undefined;" or naming an unused argument "undefined". However, I
would hope that the only cases that actually give it a new value are
those that are being intentionally malicious a la evil.js.
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