Le 02/04/2011 23:40, Brendan Eich a écrit : > On Apr 2, 2011, at 1:58 PM, David Bruant wrote: > >> I'm surprised by the idea that == could be defined on a per-value >> comparison basis on objects (Array as you give it as an example). It >> doesn't make the relation last throughout the program lifetime (which is >> what I was trying to do and requires a priori arrangements). I would >> expect an equivalence relation to last throughout the program. Like === >> does. > > The use-cases are "operators", generally. Python supports unstratified > operator meta-programming, so you can write __-delimited methods to > change the meaning of programs. This is in the Harmony agenda but not > for ES.next: > > http://wiki.ecmascript.org/doku.php?id=strawman:value_types > http://wiki.ecmascript.org/doku.php?id=strawman:value_proxies > Pythons API > <http://docs.python.org/reference/datamodel.html#emulating-numeric-types> > Virtual Values for Language Extension > <http://www.soe.ucsc.edu/research/report?ID=1595> > > It needs more baking. The value proxies idea is nearest but stratifed > and constrained, aimed at efficient implementation of new numeric > types. The ability to add operators to existing objects is not > well-explored yet. > For a non-operator-syntax proposal to add lexically scoped methods as > extensions to standard objects, using weakmaps under the hood (but observably > in that the extended object could be frozen), see > > http://wiki.ecmascript.org/doku.php?id=strawman:scoped_object_extensions > > (This page needs to be linked from > http://wiki.ecmascript.org/doku.php?id=strawman:strawman still.) > > The advantage is that independent modules can cooperate without a prior > arrangements or collisions. I have the feeling that none of these can help out with multiple inheritance. This is the problem I want to address. Equivalence classes through == and instanceof tweak were just one idea to address it.
It's not the first time that I try to address multiple inheritance and that no one really answers on this particular question, so I think I should ask the question directly instead of proposing ideas on the topic: Is multiple inheritance a use case that TC39 intends to address in a generic manner? If so, what are the current tracks? If not, I promise, I won't bother on the topic anymore :-) Regards, David
_______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
