Forward ranges in Phobos v2

[H. S. Teoh]

On Tue, Nov 02, 2021 at 04:17:06PM -0400, Andrei Alexandrescu via Digitalmars-d wrote:
> On 2021-11-02 15:32, Adam D Ruppe wrote:
> > On Tuesday, 2 November 2021 at 18:09:55 UTC, H. S. Teoh wrote:
> > > Why is this necessary?  I thought we're getting rid of
> > > std.range.interfaces.
> > 
> > It is actually really, really, useful. If phobos didn't offer it,
> > someone would reinvent it anyway.
> > 
> > (In fact, there's a lot of cases where using them is more efficient
> > than generating more and more code...)
> 
> Yah, polymorphism has its place. The only problem is passing around
> reference ranges. They should have a thin struct wrapper that carries
> the proper copy semantics.

Yes, so we need a standard way of constructing such wrappers.  Possibly
an addition to stdv2.range.interfaces?  Or maybe just have the wrapper
constructors return the constructed polymorphic range
pre-(shrink)wrapped. :-)


T

-- 
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