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Subject: Re: std::make_shared and type deduction
From: Thiago Macieira (thiago_at_[hidden])
Date: 2020-07-08 13:51:34


On Tuesday, 7 July 2020 11:37:03 PDT Kyle Knoepfel via Std-Discussion wrote:
> I routinely encounter situations where objects must be owned by (smart)
> pointer, but the means in which the pointee is constructed is not under my
> control. For example:
>
> namespace external_library {
> template <typename T>
> Foo<T> make_foo();
> }

This is not a good example because make_foo did not return a pointer. It
returned an object by value. Therefore, when you do:

> auto foo_ptr = std::make_unique<Foo<int>>(external_library::make_foo());

The pointee is constructed fully in your control. You're creating a copy of
Foo<int> and saving that in a unique_ptr.

But note how Foo<int> can be copied. So are you sure you need unique_ptr in
the first place?

-- 
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
   Software Architect - Intel System Software Products

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