[Bug libstdc++/119744] [C++23] Implement P2711R1, Making multi-param constructors of views explicit

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119744

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Nathan Myers <ncm@gcc.gnu.org>:

https://gcc.gnu.org/g:a77146f01563b5df19e70061dc237178b5532aa9

commit r16-3997-ga77146f01563b5df19e70061dc237178b5532aa9
Author: Nathan Myers <ncm@cantrip.org>
Date:   Thu Jul 3 17:15:40 2025 -0400

    libstdc++: Add NTTP bind_front, -back, not_fn (P2714) [PR119744]

    Add non-type template parameter function-object/-pointer argument
    versions of bind_front, bind_back, and not_fn.

    This introduces a new internal type _Bind_fn_t to carry the
    template-argument function object when no arguments are bound,
    used in both bind_front and bind_back. Otherwise they return
    a lambda object that has captured the arguments.

    There is no need to change libstdc++-v3/src/c++23/std.cc.in
    because existing exports: "using std::bind_front;" etc. export
    the new overloads.

    libstdc++-v3/ChangeLog:
            PR libstdc++/119744
            * include/bits/version.def: Redefine __cpp_lib_bind_front etc.
            * include/bits/version.h: Ditto.
            * include/std/functional: Add new bind_front etc. overloads
            * testsuite/20_util/function_objects/bind_back/1.cc:
            Check plumbing better
            * testsuite/20_util/function_objects/bind_back/nttp.cc: New test.
            * testsuite/20_util/function_objects/bind_back/nttp_neg.cc: New
test.
            * testsuite/20_util/function_objects/bind_front/1.cc:
            Check plumbing better
            * testsuite/20_util/function_objects/bind_front/nttp.cc: New test.
            * testsuite/20_util/function_objects/bind_front/nttp_neg.cc: New
test.
            * testsuite/20_util/function_objects/not_fn/nttp.cc: New test.
            * testsuite/20_util/function_objects/not_fn/nttp_neg.cc: New test.
            * testsuite/20_util/headers/functional/synopsis.cc: New decls.