Implementation of `three_way_comparable` and `three_way_comparable_with` concepts from <compare> header.
Please note that I have temporarily removed `<compare>` header from `<utility>` due to cyclic dependency that prevents using `<concepts>` header in `<compare>` one.
I tried to quickly resolve those issues including applying suggestions from @cjdb and dive deeper by myself but the problem seems more complicated that we thought initially.
I am in progress to prepare the patch with resolving this cyclic dependency between headers but for now I decided to put all that I have to the review to unblock people that depend on that functionality. At first glance the patch with resolving cyclic dependency is not so small (unless I find the way to make it smaller and cleaner) so I don't want to mix everything to one review.
Reviewed By: ldionne, cjdb, #libc, Quuxplusone
Differential Revision: https://reviews.llvm.org/D103478
`<type_traits>` was included in the first iteration of `<compare>` when
it was created as a monolithic header, then never removed. Removing it
now is a beneficial no-op since it is not guaranteed by the standard
and is already included by all of its subheaders.
Reviewed By: cjdb, #libc, Quuxplusone
Differential Revision: https://reviews.llvm.org/D107801
D85051's honeypot solution was a bit too aggressive swallowed up the
comparison types, which made comparing objects of different ordering
types ambiguous.
Depends on D101707.
Differential Revision: https://reviews.llvm.org/D101708
The standard leaves it up to the implementation to decide whether or not
these operators are hidden friends. There are several (well-documented)
reasons to prefer hidden friends, as well as an argument for improved
readability.
Depends on D100342.
Differential Revision: https://reviews.llvm.org/D101707
* `operator!=` isn't in the spec
* `<compare>` is designed to work with `operator<=>` so it doesn't
really make sense to have `operator<=>`-less friendly sections.
Depends on D100283.
Differential Revision: https://reviews.llvm.org/D100342
`weak_equality` and `strong_equality` were removed before being
standardised, and need to be removed.
Also adjusts `common_comparison_category` since its test needed
adjusting due to the equality deletions.
Differential Revision: https://reviews.llvm.org/D100283
This refactor is not only a good idea, but is in fact required by the standard,
in the sense that <array> is mandated to include <compare>.
So <compare> shouldn't have a circular dependency on <array>!
Differential Revision: https://reviews.llvm.org/D99307
I used a lot of `git grep` to find places where `std::` was being used
outside of comments and assert-messages. There were three outcomes:
- Qualified function calls, e.g. `std::move` becomes `_VSTD::move`.
This is the most common case.
- Typenames that don't need qualification, e.g. `std::allocator` becomes `allocator`.
Leaving these as `_VSTD::allocator` would also be fine, but I decided
that removing the qualification is more consistent with existing practice.
- Names that specifically need un-versioned `std::` qualification,
or that I wasn't sure about. For example, I didn't touch any code in
<atomic>, <math.h>, <new>, or any ext/ or experimental/ headers;
and I didn't touch any instances of `std::type_info`.
In some deduction guides, we were accidentally using `class Alloc = typename std::allocator<T>`,
despite `std::allocator<T>`'s type-ness not being template-dependent.
Because `std::allocator` is a qualified name, this did parse as we intended;
but what we meant was simply `class Alloc = allocator<T>`.
Differential Revision: https://reviews.llvm.org/D92250
* Use an empty struct instead of a member pointer to represent this
type, so that we don't actually pass a zero member pointer at runtime.
* Mark the constructor as consteval to ensure that no code is emitted
for it whenever possible.
* Add a honeypot constructor to reject all non-int arguments, so that
the only argument that can arrive at the real constructor is the
literal 0.
This results in better generated code, and rejecting invalid comparisons
against nullptr, 0L, and so on, while also rejecting invalid comparisons
against (1-1) and similar that would be allowed if we required an
integer constant expression with value 0.
Differential Revision: https://reviews.llvm.org/D85051
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351648
Summary:
Many operators in <compare> were _defined_ with the proper visibility attribute,
but they were _declared_ without any. This is not a problem until we change the
definition of _LIBCPP_INLINE_VISIBILITY to something that requires the
declaration to be decorated.
I also marked `strong_equality::operator weak_equality()` as
`_LIBCPP_INLINE_VISIBILITY`, since it seems like it had been forgotten.
This came up while trying to get rid of `__attribute__((__always_inline__))`
in favor of `__attribute__((internal_linkage))`.
Reviewers: EricWF, mclow.lists
Subscribers: christof, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D49104
llvm-svn: 336665
this patch adds the <compare> header and implements all of it
except for [comp.alg].
As I understand it, the header is needed by the compiler in
when implementing the semantics of operator<=>. For that reason
I feel it's important to land this header early, despite
all compilers lacking support.
llvm-svn: 329460
Ruslan Arutyunyan