Talk:cpp/concepts/Same

Hi all,

In the draft Same<> is defined as:

7.3.2 Concept Same [concepts.lib.corelang.same]

template  concept bool Same = is_same::value;

AFAI understand

1. this leaves no room for "possible implementation" => we would delete this part.

2. since is_same::value is associative ( is_same::value == is_same::value ), no need to care about associativity in any implementation.

Or am I wrong?

Regards, --LeslieN (talk) 07:56, 3 July 2018 (PDT)


 * I think the the use of detail::SameHelper is needed to ensure that " subsumes and vice versa. " --183.212.172.182 09:18, 3 July 2018 (PDT)
 * Correct. The TS's specification is filled with "need not be any subsumption" weasel-wording so that implementers don't need to use the exact form specified. The IS WP doesn't need that because the subsumption rules were changed so that the expression used is not observable to the user. T. Canens (talk) 03:12, 4 July 2018 (PDT)


 * Hm, well the original intent of detail::SameHelper was clear for me.
 * "The IS WP doesn't need that because the subsumption rules were changed so that the expression used is not observable to the user." Sorry T. Canens, I don't understand this sentence, can you please explain? What do you mean by "IS WP", please?
 * I think you wanted to point out that basically that the
 * template  concept bool Same = is_same::value;
 * line was ONLY suggestion, how Same can be implemented, but not mandatory. Am I right?