Le 27 oct. 2014 à 17:45, Mark S. Miller <[email protected]> a écrit :
> On Mon, Oct 27, 2014 at 7:00 AM, Andreas Rossberg <[email protected]> wrote: > > Otherwise, we need to somehow recover the functionality we lost when we gave > up the opt_useKeyLifetime flag. Given where we are, I propose another pair of > weak-map & weak-set collections, with exactly the same contract as the > current ones, except: > > * The new weak collections would have no .clear method. > * The hidden fields generated on the keys by the new weak collections would > be expected to have their full key's lifetime, whether on not the key > outlives the weak collection. I propose to define something: * with a name that corresponds to the purpose; for example "HiddenField" instead of "WeakMap". Or even "PrivateField", which is in fact more restrictive than what you can get with a plain WeakMap (more below); * with method names that agree with the transposed representation; maybe: `.getFrom()`, `.setFrom()`, `.deleteFrom()`. Compare: weakmap.get(key) vs privatefield.getFrom(object) object::privatefield Also, we must be careful not to consider WeakMaps as a way to achieve privacy (at least without wrapping the WeakMap). A map that holds weakly its key/value association without making the GC observable, must provide **hidenness** (you couldn't get a key/value pair if you don't have a prior reference to the key), but not **privacy**, as you can imagine methods on a weak map, such as `.clear()` or `.fill()`, that alter key/value pairs without mandating prior reference to keys and without making the GC observable. —Claude _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
