please approval my patch - add new logical traits to type_traits for logical completeness

[李苏旺]

hi Marc,
    I am very glad to receive you reply, in fact , I have neither "  C++
standard these are specified" nor "feature test macro" , I saw negation,
conjunction and disjunction have added in type_traits , and similar , after
I reference to
https://whatis.techtarget.com/definition/logic-gate-AND-OR-XOR-NOT-NAND-NOR-and-XNOR#xnor
  , I think  XOR(exclusive_or), NAND(not_conjunction),
NOR(not_disjunction), XNOR(not_exclusive_or) can be added in type_traits ,
that is all . any way , thank you reminder , maybe I may write a proposal
in the future , I hope these logical gates can be added too

your sincere
lisuwang


Marc Glisse <marc.glisse@inria.fr> 于2019年2月9日周六 下午3:14写道：

> (removing gcc-testresults@ which is for (automated) results of running
> the
> testsuite, not for patch submission)
>
> On Sat, 9 Feb 2019, 李苏旺 wrote:
>
> >     I have a patch about libstdc++
> > include/std/type_traits ,
> > testsuite/20_util/logical_traits/requirements/explicit_instantiation.cc
> > testsuite/20_util/logical_traits/requirements/typedefs.cc
> > testsuite/20_util/logical_traits/value.cc,
> > the patch want to add new logical traits , such as exclusive_or ,
> > not_exclusive_or, not_conjunction and not_disjunction for logical
> > completeness , the detail patch as below:
>
> Hello,
>
> could you say where in the C++ standard these are specified? What paper
> added them, and what is the corresponding feature macro? If those are
> traits that you invented yourself, you will need to get them into the
> standard before we can add them to libstdc++.
>
> --
> Marc Glisse
>