Brendan, Just wanted to say that as I gather information about this and other ES.next APIs, these points of clarification are really appreciated - thanks again.
Rick On Sun, May 15, 2011 at 2:36 PM, Brendan Eich <[email protected]> wrote: > On May 15, 2011, at 11:20 AM, Rick Waldron wrote: > > Thanks Brendan, I was looking for something that was representative of > Boris's use-case, but I appreciate the snippet none-the-less. > > > Sorry, I should have realized what you were after (although in our gist > discussion I thought I addressed it :-P). > > > I should clarify my intentions; while your example is very straight > forward, it's also as ambiguous as the gist I had originally posted that > Alex, yourself and I shared a discussion on - only in that it doesn't > illustrate the behaviour of the weakmap that has had a nulled key, post-GC. > > > As noted, you can't illustrate that difference without exposing the > non-determistic GC schedule. We don't want to do that. With an #ifdef DEBUG, > REPL/console-only hook, we could. > > > I'm coming at this from the perspective of an js application developer and > thinking "how do I synthesize this into something that developers can > understand the benefit of and apply to real-world uses?", in short: > developer education/relations. > > > It's more of a "use this unless you really know what you are doing with > strong references". Using Map by default is going to make leaks in the real > world, guaranteed. Using WeakMap when in doubt will cost a bit more but > avoid leaks. > > /be > > > > Either way, thanks again! > > Rick > > > On Sun, May 15, 2011 at 2:02 PM, Brendan Eich <[email protected]> wrote: > >> On May 14, 2011, at 6:06 PM, Rick Waldron wrote: >> >> Boris, >> >> Would you mind sharing a piece of working code (as in, runs in the latest >> Firefox Nightly) that demonstrates your example in a real world scenario? >> This would be greatly appreciated >> >> >> javascript:k = {}; v = "hi"; w = WeakMap(); w.set(k, v); alert(w.get(k)) >> >> just alerted "hi" in my slightly out of date tracemonkey-repo nightly >> build. There may be some javascript: URL stripping or blocking you have to >> get past, in which case use the code after the javascript: in the Web >> Console. >> >> /be >> >> >> >> Rick >> >> On Sat, May 14, 2011 at 8:55 PM, Boris Zbarsky <[email protected]> wrote: >> >>> On 5/14/11 6:37 PM, Oliver Hunt wrote: >>> >>>> Can you provide a use case where you have an object key as the usual >>>> programming idiom? >>>> >>> >>> Attaching metadata to object without polluting the objects themselves. >>> >>> For example, Firefox extensions want to do this all the time for various >>> DOM objects (and especially Window). >>> >>> -Boris >>> >>> _______________________________________________ >>> es-discuss mailing list >>> [email protected] >>> https://mail.mozilla.org/listinfo/es-discuss >>> >> >> _______________________________________________ >> es-discuss mailing list >> [email protected] >> https://mail.mozilla.org/listinfo/es-discuss >> >> >> > >
_______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
