es-discuss Digest, Vol 41, Issue 9

[Leo Meyerovich]

On Jul 4, 2010, at 12:30 AM, Brendan Eich wrote:

> On Jul 3, 2010, at 10:27 PM, Leo Meyerovich wrote:
> 
>> Is object identity the inverse of hash?
> 
> No, merely the missing-from-the-standard-library egal function that you can write yourself. See
> 
> http://wiki.ecmascript.org/doku.php?id=strawman:egal
> 


... then I still don't see how to do an encoding of weak references that isn't invasive (e.g., adding in a user-level GC that constructors are somehow guaranteed to go through). For a non-invasive approach, there might be probablistic guarantees achieved by API restrictions (e.g., limit the number of bad guesses of IDs for the otherwise forgeable ID->object function) or a creative use of lexically scoped regions, but I'm skeptical of anything complicated like that. 

Did you have something in mind in how hashes (or some other feature) enable weak references / dictionaries? It didn't jump out at me and I want them :)

- Leo