On May 16, 2011, at 1:52 AM, Erik Corry wrote: > My question was, do the use cases have both the GC of the map and the > key triggering the GC of the value or is the GC of the key the > important one and GC of the map not that common/important etc.
I'm not sure, we will have to measure to give a quantitative answer. But consider this: weak maps are used with membranes and "vats", and both the wrapped object (a key into a weak map handling out-of-vat object wrapping) and the whole vat can go away. Think window.close or DOM iframe creation/destruction via navigation. > For the use case mentioned by Boris in this thread, where a FF > extension needs to attach metadata to an object it doesn't seem likely > that the mapping will get lost and need to be GCed before the objects > that have the metadata attached. The add-on easily can outlive the content window or iframe containing the wrapped object, you're right. But it can go the other way too: add-on disabling or add-on specific reset clears the add-on state, including weak maps, while the content DOM wrapped objects live blithely on. /be _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
