es-discuss Digest, Vol 43, Issue 1

Brendan Eich brendan at
Thu Sep 2 00:29:25 PDT 2010

On Sep 2, 2010, at 12:08 AM, Leo Meyerovich wrote:

> That said, going back to the beginning: deterministic GC-independent semantics are a Good Thing. Whether this matters seems to be a crucial discussion. Is there a concern for basic correctness for more mundane code? Are those use cases similar to the above where a 'strictness' library suffices? Again, I'd point to the ActionScript experience for a reference: can anybody attack or break a flash program with weak maps, or is this FUD? I'm more concerned about the dangers of misuse in terms of memory leaks and event-oriented logic glitches between code running on different ES implementations (and suspect the answer has a reasonable chance of being 'yes' for these).

I tend to agree that the answer is 'yes', assuming the question was "Whether [deterministic GC-independent semantics] matters" ;-).

It's hard to make an airtight case for "security" even on a good day, but removing observability from the weak maps proposal makes it strictly simpler and less likely to cause any number of problems. I don't believe that lack of enumerability and .length cripples the API for the intended use cases of soft fields, membrane caches, and the like.


More information about the es-discuss mailing list