Re: [boost] Adding polymorphic_value to boost

Subject: Re: [boost] Adding polymorphic_value to boost
From: Jonathan Coe (jonathanbcoe_at_[hidden])
Date: 2017-11-20 19:12:41

> On 20 Nov 2017, at 18:29, Zach Laine via Boost <boost_at_[hidden]> wrote:
> 
> On Mon, Nov 20, 2017 at 12:23 PM, Jonathan Coe via Boost <
> boost_at_[hidden]> wrote:
> 
>>> On 20 Nov 2017, at 17:59, Peter Dimov via Boost <boost_at_[hidden]>
>> wrote:
>>> 
>>> Two classes instead of one is not without its downsides, since they are
>> very similar in both appearance in behavior, but on the plus side, this
>> allows us to make the interface of the pointer class unapologetically
>> pointer-like and the interface of the value class... well, as
>> value-not-pointer-like as possible, which isn't much due to op->, but
>> still. :-)
>>> 
>>> 
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>> 
>> I’m proposing adding polymorphic_value to boost, not cloned_ptr. My
>> submission to boost is intended to mirror my submission to the C++
>> standards committee.
>> 
> 
> To answer the proximate question, LEWG wanted nothing to do with clone_ptr,
> whether or not it is designed to support or interoperate with
> polymorphic_value.  Jonathan, please correct me if I'm wrong.
> 
> Zach
> 
> _______________________________________________
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Zac is correct. LEWG requested that const propagation was added to X and that it ceased to be pointer-like. I agree with their direction.

Sean (Parent) gave a rather nice talk which mentioned this at code dive 2016:
https://youtu.be/cK_kftBNgBc about 40 mins in.