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Postings from April 2022
2022-4-5 17:06 Graham Knop <haarg@haarg.org> wrote:
> On Tue, Apr 5, 2022 at 5:56 AM Yuki Kimoto <kimoto.yuki@gmail.com> wrote:
> >
> >
> >
> > 2022-4-4 19:27 Dagfinn Ilmari Mannsåker <ilmari@ilmari.org> wrote:
> >>
> >> Yuki Kimoto <kimoto.yuki@gmail.com> writes:
> >>
> >> > I ask a question about yield_true feature.
> >> >
> >> > This example seems to be adding "1;" to the end of the file scope.
> >> >
> >> > Can yield_true feature be implemented actually as a file scope, not
> as a
> >> > global scope?
> >>
> >> All features (as in feature.pm) are lexically scoped, the file scope is
> >> just the top-level lexical scope. This implies that doing `use feature
> >> 'yield_true';` in a non-toplevel scope, i.e. inside a sub or other
> >> block, has no effect, since the feature will not be enabled anymore at
> >> the end of the file scope.
> >>
> >> - ilmari
> >
> >
> > Thank you for your reply.
> >
> > Can I understand the yield_true feature as the following example?
> >
> > {
> > use feature 'yield_true';
> > {
> > print "Hello';
> > }
> > }
> >
> > is same as
> >
> > {
> > {
> > print "Hello';
> > }
> > 1;
> > }
> >
>
> It wouldn't make any sense for this to apply to inner blocks. It would
> only apply to the end of the file. Since the feature would usually be
> enabled at the beginning of a file, it would be in effect for all
> inner blocks. Having all inner blocks in a file return true would not
> make sense.
>
> There is more discussion about this potential feature on the RFC:
> https://github.com/Perl/RFCs/pull/16
Could the conversion of Pre-RFC of "yield_true" be done in another thread
of p5p?
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