A search shows some old discussions of the topic mentioning that they might be going in to future versions of the language, etc. But on the other hand I've been told in response to this question before that TC39 has a general policy against features that allow garbage collection to be visible to applications.
There's still a strawman up on the wiki: http://wiki.ecmascript.org/doku.php?id=strawman:weak_references and while it appears to be a relatively simple, sane way to expose weak references, it looks like the strawman hasn't been touched since late 2011. Is that because it's dead? Or was it deprioritized because weak references are believed to not be needed by JS application developers? I ask this because the lack of weak references (or any suitable substitute mechanism) comes up regularly when dealing with the challenge of porting native apps to JavaScript, and it leads people to consider extremely elaborate workarounds just to build working applications (like storing *all* their data in a virtual heap backed by typed arrays and running their own garbage collector against it). If there is really a firm reason why this must be so, so be it, but seeing so many people do an end-run around the JS garbage collector only to implement their own *in JavaScript* makes me wonder if perhaps something is wrong. The presence of WeakMaps makes it clear to me that solving this general class of problems is on the table. People are certainly solving this problem in other JS related contexts: https://github.com/TooTallNate/node-weak Historically the lack of weak references has resulted in various solutions in libraries like jQuery specifically designed to avoid cycles being created between event listeners and DOM objects. Many of these solutions are error-prone and require manual breaking of cycles. To make a controversial statement, I would suggest that there are some problems that cannot be solved in JavaScript unless it has an approximation of weak references. I would love to be proven wrong here because then I can use whatever your crazy computer science alternative is. :D Thanks, -kg _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
