El jue., 4 oct. 2018 21:21, Brandon Allbery <allber...@gmail.com> escribió:
> I don't think we've reached the point of such conventions yet. And there's > some history here, in --> not having done anything in the early days except > possibly slow things down, and between --> and 'returns' (which is now > deprecated). > Not yet. Maybe never... > > On Thu, Oct 4, 2018 at 3:13 PM Trey Harris <t...@lopsa.org> wrote: > >> Right; that's what I meant by "stylistically" — a `--> Mu` can highlight >> that something is being returned (and that side-effects are not the primary >> purpose), while nothing indicates that the return value, though it exists, >> is incidental and probably from "falling off the end" or using `return` as >> a control-flow jump. >> On Thu, Oct 4, 2018 at 15:04 Brandon Allbery <allber...@gmail.com> wrote: >> >>> Arguably it should be --> Any, since Mu vs. Any has meaning with respect >>> to Junctions. But in this case it's just not stating a redundancy. >>> >>> The way you'd phrased it makes it sound like it's an explicit >>> no-meaningful-result, as opposed to 'we don't know or care'. >>> >>> On Thu, Oct 4, 2018 at 3:02 PM Trey Harris <t...@lopsa.org> wrote: >>> >>>> Ah (replying to both Brandon and JJ since their replies crossed): >>>> >>>> So `--> Mu` is not a sufficient and/or correct return constraint for >>>> things like AT-POS because why, then? >>>> On Thu, Oct 4, 2018 at 14:56 Brandon Allbery <allber...@gmail.com> >>>> wrote: >>>> >>>>> I think they meant more like my AT-POS example: the point is the >>>>> return value, but you can't say ahead of time what type it will have. >>>>> >>>>> On Thu, Oct 4, 2018 at 2:48 PM Trey Harris <t...@lopsa.org> wrote: >>>>> >>>>>> >>>>>> >>>>>> On Thu, Oct 4, 2018 at 02:13 JJ Merelo <jjmer...@gmail.com> wrote: >>>>>> >>>>>>> >>>>>>> >>>>>>> El jue., 4 oct. 2018 a las 3:36, Trey Harris (<t...@lopsa.org>) >>>>>>> escribió: >>>>>>> >>>>>>>> _All_ routines in Perl 6 return _something._ A lack of a "-->" >>>>>>>> simply indicates stylistically that the return is not useful because >>>>>>>> it's >>>>>>>> whatever "falls off the end". (There's a bit of variance here as I'm >>>>>>>> not >>>>>>>> sure it's a convention everyone has followed.) It's equivalent to "--> >>>>>>>> Mu" >>>>>>>> because anything that could "fall of the end" is Mu. >>>>>>>> >>>>>>> >>>>>>> No, it means that it's not constrained to a type. It can still >>>>>>> return something, but it can be anything. >>>>>>> >>>>>> >>>>>> >>>>>> I get all that, except for the "No" at the front. ;-) >>>>>> >>>>>> Or were you talking about the "not useful" bit? Yes, of course in any >>>>>> given codebase, the lack of a return value has no more or less meaning >>>>>> than >>>>>> a lack of any constraint. The programmer may not like using constraints >>>>>> at >>>>>> all and treats Perl 6 like Perl 5 in the respect of wanting arbitrarily >>>>>> mungible values. >>>>>> >>>>>> But the word "stylistically" was important, as I was responding to >>>>>> Todd's question about the docs—I think a lack of a return value in the >>>>>> docs >>>>>> (at least, the ones I could come up with in a grep pattern on my checkout >>>>>> of docs) does tend to indicate that the return is not useful, that the >>>>>> routine is a "procedure" run for its side effects rather than for >>>>>> evaluation. >>>>>> >>>>>> Is that what you meant? >>>>>> >>>>>> If you were saying in "it can still return something, but can be >>>>>> anything", that "anything ⊃ (is a strict superset of) `Mu`", then I >>>>>> don't understand, because I thought all values conformed to Mu. >>>>>> >>>>>> >>>>> >>>>> -- >>>>> brandon s allbery kf8nh >>>>> allber...@gmail.com >>>>> >>>> >>> >>> -- >>> brandon s allbery kf8nh >>> allber...@gmail.com >>> >> > > -- > brandon s allbery kf8nh > allber...@gmail.com >
