Well bummer. Thanks for the detailed info. Perhaps someday it can check if they do directly extend Object or not and either take the shortcut or the long way... I'm afraid that's way over my depth in the GWT code to attempt a patch though.
On Wednesday, May 11, 2016 at 6:07:15 PM UTC-7, Ray Cromwell wrote: > > The issue is that @JsFunction implementors must "extend > java.lang.Object" as their parent. because standard library functions > are/canbe implemented on classes with complicated type hierarchies, > this would cause failures to compile. > > This restriction comes about from the efficiency trick we use to > reparent a lambda to have the native JS Function object as it's > parent. We can't reparent objects whose immediate supertype isn't > java.lang.Object, but not doing this trick would make output more > bloated/slow, and wouldn't allow Java8 lambas to act like JS functions > (e.g. can call Function.bind/apply/etc on them) without some kind of > wrapping/unwrapping process, plus an additional level of hacks to make > sure referential integrity was preserved. > > > > > On Wed, May 11, 2016 at 5:51 PM, Colin Alworth <[email protected] > <javascript:>> wrote: > > No, its not a solution, so much as a "here is a workaround that might > > satisfy your specific case as you build your JsInterop-based lib so that > it > > looks like it can use @FunctionalInterface types". I do not believe it > to be > > a comprehensive way to provide the feature requested. At some point I'll > try > > to write it out in more detail in case there is any actual merit to it > (I'm > > all but sure that there isn't, or you would have thought of it already). > > > > On Wed, May 11, 2016 at 7:47 PM 'Goktug Gokdogan' via GWT Contributors > > <[email protected] <javascript:>> wrote: > >> > >> We cannot impose @JsFunction restrictions on standard library > >> @FunctionInterfaces. You can see some of the limitations in the > Javadoc. > >> > >> @Colin: I didn't understand your solution. Feel free to propose > something > >> more concrete and we can discuss over that. > >> > >> On Wed, May 11, 2016 at 4:22 PM, Colin Alworth <[email protected] > <javascript:>> wrote: > >>> > >>> Unfortunately, you can't add the annotation to an interface with more > >>> than one method, even if those methods are default methods, at least > as it > >>> is currently implemented. > >>> > >>> I can't remember the exact specifics around why this is the case, but > >>> believe it has to do with handling functions passed from js into java, > and > >>> not being able to nicely handle instances that decide to override > those > >>> other methods as well. > >>> > >>> You could nearly achieve this effect by just making a method reference > to > >>> the "apply" or "test" method, and passing that as an actual JsFunction > type. > >>> I don't right away see a problem with syntactic sugar doing this > >>> automatically, but am sure that someone will be able to enlighten us > as to > >>> what confusing side effects this might have (or alternately confirm > that > >>> this is a great idea, and point to where in the compiler the changes > need to > >>> be made). > >>> > >>> > >>> On Wed, May 11, 2016, 6:15 PM David Becker <[email protected] > <javascript:>> > >>> wrote: > >>>> > >>>> I think it would be good to add @JsFunction to all of the > >>>> java.util.function interfaces in the JRE Emulation so that we can use > >>>> standard function signatures with JsInterop. > >>>> > >>>> Would that work? Any drawbacks? > >>>> > >>>> If you think that's a good idea, I can submit a patch. > >>>> > >>>> Thanks! > >>>> > >>>> -- > >>>> You received this message because you are subscribed to the Google > >>>> Groups "GWT Contributors" group. > >>>> To unsubscribe from this group and stop receiving emails from it, > send > >>>> an email to > [email protected] <javascript:>. > > >>>> To view this discussion on the web visit > >>>> > https://groups.google.com/d/msgid/google-web-toolkit-contributors/13df9bed-108f-4cdf-8c00-123f1186e461%40googlegroups.com. > > > >>>> For more options, visit https://groups.google.com/d/optout. > >>> > >>> -- > >>> You received this message because you are subscribed to the Google > Groups > >>> "GWT Contributors" group. > >>> To unsubscribe from this group and stop receiving emails from it, send > an > >>> email to [email protected] > <javascript:>. > >>> > >>> To view this discussion on the web visit > >>> > https://groups.google.com/d/msgid/google-web-toolkit-contributors/CADcXZMzaxRmFrvZUkQMG0VQETyJo5TWmjtFqPsn3msrBBvvLGg%40mail.gmail.com. > > > >>> > >>> > >>> For more options, visit https://groups.google.com/d/optout. > >> > >> -- > >> You received this message because you are subscribed to the Google > Groups > >> "GWT Contributors" group. > >> To unsubscribe from this group and stop receiving emails from it, send > an > >> email to [email protected] > <javascript:>. > >> To view this discussion on the web visit > >> > https://groups.google.com/d/msgid/google-web-toolkit-contributors/CAN%3DyUA0CktOO8rpggbAcfPyTPhP7bp3fOTZgxSZiWyGq09waBw%40mail.gmail.com. > > > >> For more options, visit https://groups.google.com/d/optout. > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "GWT Contributors" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to [email protected] > <javascript:>. > > To view this discussion on the web visit > > > https://groups.google.com/d/msgid/google-web-toolkit-contributors/CADcXZMwvRokmP5nq84jmE40Dmos3eMmPDH-V4RcCz-%2BjbubvxQ%40mail.gmail.com. > > > > > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "GWT Contributors" group. 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