What is the difference to static_cast<unsigned int>(size())

(or some suitably longer <size_t> type)

Or you want to definitely have functions differentiated (overloaded) by return type?

-----Ursprüngliche Nachricht-----
Von: Frederick Virchanza Gotham via Std-Proposals <std-proposals@lists.isocpp.org>
Gesendet: Do 09.10.2025 13:43
Betreff: Re: [std-proposals] ranges::size should always return a unsigned integer
An: std-proposals@lists.isocpp.org;
CC: Frederick Virchanza Gotham <cauldwell.thomas@gmail.com>;


On Wednesday, October 8, 2025, Yexuan Xiao wrote:

Why is it allowed to return a signed integer? C++ users are accustomed to the fact that the size_type of containers is an unsigned integer, so the size of containers should also return an unsigned integer.

 

 

 

 - - - - - - - Begin Half-baked Idea  - - - - - - -

 

 

What if we could define a function (or member function) as follows:

 

    +|- int size(void);

 

The trigraph,   +|-  , at the beginning indicates that the function has two forms: one returning signed, and one returning unsigned.

 

So then when you want to invoke the function, you get the unsigned version as follows:

 

    auto x = size();

 

and you get the signed version as follows:

 

    auto x = +|- size();

 

Similarly you would ake the address of the function as follows:

 

    int (*p1)(void) = &size;

    unsigned (*p2)(void) = & +|- size;

 

I would add the stipulation that both of these function pointers can compare equal (because they'll most likely have the same machine code anyway since Two's Complement is now mandatory).

-- 
 Std-Proposals mailing list
 Std-Proposals@lists.isocpp.org
 https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals