Files
freebsd/contrib/libc++/include/variant
T
Dimitry Andric e8948c9522 Merge clang, llvm, lld, lldb, compiler-rt and libc++ 5.0.0 release.
MFC r309126 (by emaste):

  Correct lld llvm-tblgen dependency file name

MFC r309169:

  Get rid of separate Subversion mergeinfo properties for llvm-dwarfdump
  and llvm-lto.  The mergeinfo confuses Subversion enormously, and these
  directories will just use the mergeinfo for llvm itself.

MFC r312765:

  Pull in r276136 from upstream llvm trunk (by Wei Mi):

    Use ValueOffsetPair to enhance value reuse during SCEV expansion.

    In D12090, the ExprValueMap was added to reuse existing value during
    SCEV expansion. However, const folding and sext/zext distribution can
    make the reuse still difficult.

    A simplified case is: suppose we know S1 expands to V1 in
    ExprValueMap, and
      S1 = S2 + C_a
      S3 = S2 + C_b
    where C_a and C_b are different SCEVConstants. Then we'd like to
    expand S3 as V1 - C_a + C_b instead of expanding S2 literally. It is
    helpful when S2 is a complex SCEV expr and S2 has no entry in
    ExprValueMap, which is usually caused by the fact that S3 is
    generated from S1 after const folding.

    In order to do that, we represent ExprValueMap as a mapping from SCEV
    to ValueOffsetPair. We will save both S1->{V1, 0} and S2->{V1, C_a}
    into the ExprValueMap when we create SCEV for V1. When S3 is
    expanded, it will first expand S2 to V1 - C_a because of S2->{V1,
    C_a} in the map, then expand S3 to V1 - C_a + C_b.

    Differential Revision: https://reviews.llvm.org/D21313

  This should fix assertion failures when building OpenCV >= 3.1.

  PR:		215649

MFC r312831:

  Revert r312765 for now, since it causes assertions when building
  lang/spidermonkey24.

  Reported by:	antoine
  PR:		215649

MFC r316511 (by jhb):

  Add an implementation of __ffssi2() derived from __ffsdi2().

  Newer versions of GCC include an __ffssi2() symbol in libgcc and the
  compiler can emit calls to it in generated code.  This is true for at
  least GCC 6.2 when compiling world for mips and mips64.

  Reviewed by:	jmallett, dim
  Sponsored by:	DARPA / AFRL
  Differential Revision:	https://reviews.freebsd.org/D10086

MFC r318601 (by adrian):

  [libcompiler-rt] add bswapdi2/bswapsi2

  This is required for mips gcc 6.3 userland to build/run.

  Reviewed by:	emaste, dim
  Approved by:	emaste
  Differential Revision:	https://reviews.freebsd.org/D10838

MFC r318884 (by emaste):

  lldb: map TRAP_CAP to a trace trap

  In the absense of a more specific handler for TRAP_CAP (generated by
  ENOTCAPABLE or ECAPMODE while in capability mode) treat it as a trace
  trap.

  Example usage (testing the bug in PR219173):

  % proccontrol -m trapcap lldb usr.bin/hexdump/obj/hexdump -- -Cv -s 1 /bin/ls
  ...
  (lldb) run
  Process 12980 launching
  Process 12980 launched: '.../usr.bin/hexdump/obj/hexdump' (x86_64)
  Process 12980 stopped
  * thread #1, stop reason = trace
      frame #0: 0x0000004b80c65f1a libc.so.7`__sys_lseek + 10
  ...

  In the future we should have LLDB control the trapcap procctl itself
  (as it does with ASLR), as well as report a specific stop reason.
  This change eliminates an assertion failure from LLDB for now.

MFC r319796:

  Remove a few unneeded files from libllvm, libclang and liblldb.

MFC r319885 (by emaste):

  lld: ELF: Fix ICF crash on absolute symbol relocations.

  If two sections contained relocations to absolute symbols with the same
  value we would crash when trying to access their sections. Add a check that
  both symbols point to sections before accessing their sections, and treat
  absolute symbols as equal if their values are equal.

  Obtained from:	LLD commit r292578

MFC r319918:

  Revert r319796 for now, it can cause undefined references when linking
  in some circumstances.

  Reported by:	Shawn Webb <[email protected]>

MFC r319957 (by emaste):

  lld: Add armelf emulation mode

  Obtained from:	LLD r305375

MFC r321369:

  Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
  5.0.0 (trunk r308421).  Upstream has branched for the 5.0.0 release,
  which should be in about a month.  Please report bugs and regressions,
  so we can get them into the release.

  Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
  support to build; see UPDATING for more information.

MFC r321420:

  Add a few more object files to liblldb, which should solve errors when
  linking the lldb executable in some cases.  In particular, when the
  -ffunction-sections -fdata-sections options are turned off, or
  ineffective.

  Reported by:	Shawn Webb, Mark Millard

MFC r321433:

  Cleanup stale Options.inc files from the previous libllvm build for
  clang 4.0.0.  Otherwise, these can get included before the two newly
  generated ones (which are different) for clang 5.0.0.

  Reported by:	Mark Millard

MFC r321439 (by bdrewery):

  Move llvm Options.inc hack from r321433 for NO_CLEAN to lib/clang/libllvm.

  The files are only ever generated to .OBJDIR, not to WORLDTMP (as a
  sysroot) and are only ever included from a compilation.  So using
  a beforebuild target here removes the file before the compilation
  tries to include it.

MFC r321664:

  Pull in r308891 from upstream llvm trunk (by Benjamin Kramer):

    [CodeGenPrepare] Cut off FindAllMemoryUses if there are too many uses.

    This avoids excessive compile time. The case I'm looking at is
    Function.cpp from an old version of LLVM that still had the giant
    memcmp string matcher in it. Before r308322 this compiled in about 2
    minutes, after it, clang takes infinite* time to compile it. With
    this patch we're at 5 min, which is still bad but this is a
    pathological case.

    The cut off at 20 uses was chosen by looking at other cut-offs in LLVM
    for user scanning. It's probably too high, but does the job and is
    very unlikely to regress anything.

    Fixes PR33900.

    * I'm impatient and aborted after 15 minutes, on the bug report it was
      killed after 2h.

  Pull in r308986 from upstream llvm trunk (by Simon Pilgrim):

    [X86][CGP] Reduce memcmp() expansion to 2 load pairs (PR33914)

    D35067/rL308322 attempted to support up to 4 load pairs for memcmp
    inlining which resulted in regressions for some optimized libc memcmp
    implementations (PR33914).

    Until we can match these more optimal cases, this patch reduces the
    memcmp expansion to a maximum of 2 load pairs (which matches what we
    do for -Os).

    This patch should be considered for the 5.0.0 release branch as well

    Differential Revision: https://reviews.llvm.org/D35830

  These fix a hang (or extremely long compile time) when building older
  LLVM ports.

  Reported by:    antoine
  PR:             219139

MFC r321719:

  Pull in r309503 from upstream clang trunk (by Richard Smith):

    PR33902: Invalidate line number cache when adding more text to
    existing buffer.

    This led to crashes as the line number cache would report a bogus
    line number for a line of code, and we'd try to find a nonexistent
    column within the line when printing diagnostics.

  This fixes an assertion when building the graphics/champlain port.

  Reported by:	antoine, kwm
  PR:		219139

MFC r321723:

  Upgrade our copies of clang, llvm, lld and lldb to r309439 from the
  upstream release_50 branch.  This is just after upstream's 5.0.0-rc1.

MFC r322320:

  Upgrade our copies of clang, llvm and libc++ to r310316 from the
  upstream release_50 branch.

MFC r322326 (by emaste):

  lldb: Make i386-*-freebsd expression work on JIT path

  * Enable i386 ABI creation for freebsd
  * Added an extra argument in ABISysV_i386::PrepareTrivialCall for mmap
    syscall
  * Unlike linux, the last argument of mmap is actually 64-bit(off_t).
    This requires us to push an additional word for the higher order bits.
  * Prior to this change, ktrace dump will show mmap failures due to
    invalid argument coming from the 6th mmap argument.

  Submitted by:	Karnajit Wangkhem
  Differential Revision:	https://reviews.llvm.org/D34776

MFC r322360 (by emaste):

  lldb: Report inferior signals as signals, not exceptions, on FreeBSD

  This is the FreeBSD equivalent of LLVM r238549.

  This serves 2 purposes:

  * LLDB should handle inferior process signals SIGSEGV/SIGILL/SIGBUS/
    SIGFPE the way it is suppose to be handled. Prior to this fix these
    signals will neither create a coredump, nor exit from the debugger
    or work for signal handling scenario.
  * eInvalidCrashReason need not report "unknown crash reason" if we have
    a valid si_signo

  llvm.org/pr23699

  Patch by Karnajit Wangkhem

  Differential Revision:  https://reviews.llvm.org/D35223

  Submitted by:	Karnajit Wangkhem
  Obtained from:	LLVM r310591

MFC r322474 (by emaste):

  lld: Add `-z muldefs` option.

  Obtained from:	LLVM r310757

MFC r322740:

  Upgrade our copies of clang, llvm, lld and libc++ to r311219 from the
  upstream release_50 branch.

MFC r322855:

  Upgrade our copies of clang, llvm, lldb and compiler-rt to r311606 from
  the upstream release_50 branch.

  As of this version, lib/msun's trig test should also work correctly
  again (see bug 220989 for more information).

  PR:		220989

MFC r323112:

  Upgrade our copies of clang, llvm, lldb and compiler-rt to r312293 from
  the upstream release_50 branch.  This corresponds to 5.0.0 rc4.

  As of this version, the cad/stepcode port should now compile in a more
  reasonable time on i386 (see bug 221836 for more information).

  PR:		221836

MFC r323245:

  Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
  5.0.0 release (upstream r312559).

  Release notes for llvm, clang and lld will be available here soon:
  <http://releases.llvm.org/5.0.0/docs/ReleaseNotes.html>
  <http://releases.llvm.org/5.0.0/tools/clang/docs/ReleaseNotes.html>
  <http://releases.llvm.org/5.0.0/tools/lld/docs/ReleaseNotes.html>

  Relnotes:	yes
2017-09-26 19:56:36 +00:00

1565 lines
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C++

// -*- C++ -*-
//===------------------------------ variant -------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP_VARIANT
#define _LIBCPP_VARIANT
/*
variant synopsis
namespace std {
// 20.7.2, class template variant
template <class... Types>
class variant {
public:
// 20.7.2.1, constructors
constexpr variant() noexcept(see below);
variant(const variant&);
variant(variant&&) noexcept(see below);
template <class T> constexpr variant(T&&) noexcept(see below);
template <class T, class... Args>
constexpr explicit variant(in_place_type_t<T>, Args&&...);
template <class T, class U, class... Args>
constexpr explicit variant(
in_place_type_t<T>, initializer_list<U>, Args&&...);
template <size_t I, class... Args>
constexpr explicit variant(in_place_index_t<I>, Args&&...);
template <size_t I, class U, class... Args>
constexpr explicit variant(
in_place_index_t<I>, initializer_list<U>, Args&&...);
// 20.7.2.2, destructor
~variant();
// 20.7.2.3, assignment
variant& operator=(const variant&);
variant& operator=(variant&&) noexcept(see below);
template <class T> variant& operator=(T&&) noexcept(see below);
// 20.7.2.4, modifiers
template <class T, class... Args>
T& emplace(Args&&...);
template <class T, class U, class... Args>
T& emplace(initializer_list<U>, Args&&...);
template <size_t I, class... Args>
variant_alternative_t<I, variant>& emplace(Args&&...);
template <size_t I, class U, class... Args>
variant_alternative_t<I, variant>& emplace(initializer_list<U>, Args&&...);
// 20.7.2.5, value status
constexpr bool valueless_by_exception() const noexcept;
constexpr size_t index() const noexcept;
// 20.7.2.6, swap
void swap(variant&) noexcept(see below);
};
// 20.7.3, variant helper classes
template <class T> struct variant_size; // undefined
template <class T>
constexpr size_t variant_size_v = variant_size<T>::value;
template <class T> struct variant_size<const T>;
template <class T> struct variant_size<volatile T>;
template <class T> struct variant_size<const volatile T>;
template <class... Types>
struct variant_size<variant<Types...>>;
template <size_t I, class T> struct variant_alternative; // undefined
template <size_t I, class T>
using variant_alternative_t = typename variant_alternative<I, T>::type;
template <size_t I, class T> struct variant_alternative<I, const T>;
template <size_t I, class T> struct variant_alternative<I, volatile T>;
template <size_t I, class T> struct variant_alternative<I, const volatile T>;
template <size_t I, class... Types>
struct variant_alternative<I, variant<Types...>>;
constexpr size_t variant_npos = -1;
// 20.7.4, value access
template <class T, class... Types>
constexpr bool holds_alternative(const variant<Types...>&) noexcept;
template <size_t I, class... Types>
constexpr variant_alternative_t<I, variant<Types...>>&
get(variant<Types...>&);
template <size_t I, class... Types>
constexpr variant_alternative_t<I, variant<Types...>>&&
get(variant<Types...>&&);
template <size_t I, class... Types>
constexpr variant_alternative_t<I, variant<Types...>> const&
get(const variant<Types...>&);
template <size_t I, class... Types>
constexpr variant_alternative_t<I, variant<Types...>> const&&
get(const variant<Types...>&&);
template <class T, class... Types>
constexpr T& get(variant<Types...>&);
template <class T, class... Types>
constexpr T&& get(variant<Types...>&&);
template <class T, class... Types>
constexpr const T& get(const variant<Types...>&);
template <class T, class... Types>
constexpr const T&& get(const variant<Types...>&&);
template <size_t I, class... Types>
constexpr add_pointer_t<variant_alternative_t<I, variant<Types...>>>
get_if(variant<Types...>*) noexcept;
template <size_t I, class... Types>
constexpr add_pointer_t<const variant_alternative_t<I, variant<Types...>>>
get_if(const variant<Types...>*) noexcept;
template <class T, class... Types>
constexpr add_pointer_t<T>
get_if(variant<Types...>*) noexcept;
template <class T, class... Types>
constexpr add_pointer_t<const T>
get_if(const variant<Types...>*) noexcept;
// 20.7.5, relational operators
template <class... Types>
constexpr bool operator==(const variant<Types...>&, const variant<Types...>&);
template <class... Types>
constexpr bool operator!=(const variant<Types...>&, const variant<Types...>&);
template <class... Types>
constexpr bool operator<(const variant<Types...>&, const variant<Types...>&);
template <class... Types>
constexpr bool operator>(const variant<Types...>&, const variant<Types...>&);
template <class... Types>
constexpr bool operator<=(const variant<Types...>&, const variant<Types...>&);
template <class... Types>
constexpr bool operator>=(const variant<Types...>&, const variant<Types...>&);
// 20.7.6, visitation
template <class Visitor, class... Variants>
constexpr see below visit(Visitor&&, Variants&&...);
// 20.7.7, class monostate
struct monostate;
// 20.7.8, monostate relational operators
constexpr bool operator<(monostate, monostate) noexcept;
constexpr bool operator>(monostate, monostate) noexcept;
constexpr bool operator<=(monostate, monostate) noexcept;
constexpr bool operator>=(monostate, monostate) noexcept;
constexpr bool operator==(monostate, monostate) noexcept;
constexpr bool operator!=(monostate, monostate) noexcept;
// 20.7.9, specialized algorithms
template <class... Types>
void swap(variant<Types...>&, variant<Types...>&) noexcept(see below);
// 20.7.10, class bad_variant_access
class bad_variant_access;
// 20.7.11, hash support
template <class T> struct hash;
template <class... Types> struct hash<variant<Types...>>;
template <> struct hash<monostate>;
} // namespace std
*/
#include <__config>
#include <__tuple>
#include <array>
#include <exception>
#include <functional>
#include <initializer_list>
#include <new>
#include <tuple>
#include <type_traits>
#include <utility>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
namespace std { // explicitly not using versioning namespace
class _LIBCPP_EXCEPTION_ABI bad_variant_access : public exception {
public:
virtual const char* what() const _NOEXCEPT;
};
} // namespace std
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 14
_LIBCPP_NORETURN
inline _LIBCPP_INLINE_VISIBILITY
void __throw_bad_variant_access() {
#ifndef _LIBCPP_NO_EXCEPTIONS
throw bad_variant_access();
#else
_VSTD::abort();
#endif
}
template <class... _Types>
class _LIBCPP_TEMPLATE_VIS variant;
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_size;
template <class _Tp>
constexpr size_t variant_size_v = variant_size<_Tp>::value;
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_size<const _Tp> : variant_size<_Tp> {};
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_size<volatile _Tp> : variant_size<_Tp> {};
template <class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_size<const volatile _Tp>
: variant_size<_Tp> {};
template <class... _Types>
struct _LIBCPP_TEMPLATE_VIS variant_size<variant<_Types...>>
: integral_constant<size_t, sizeof...(_Types)> {};
template <size_t _Ip, class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_alternative;
template <size_t _Ip, class _Tp>
using variant_alternative_t = typename variant_alternative<_Ip, _Tp>::type;
template <size_t _Ip, class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, const _Tp>
: add_const<variant_alternative_t<_Ip, _Tp>> {};
template <size_t _Ip, class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, volatile _Tp>
: add_volatile<variant_alternative_t<_Ip, _Tp>> {};
template <size_t _Ip, class _Tp>
struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, const volatile _Tp>
: add_cv<variant_alternative_t<_Ip, _Tp>> {};
template <size_t _Ip, class... _Types>
struct _LIBCPP_TEMPLATE_VIS variant_alternative<_Ip, variant<_Types...>> {
static_assert(_Ip < sizeof...(_Types), "Index out of bounds in std::variant_alternative<>");
using type = __type_pack_element<_Ip, _Types...>;
};
constexpr size_t variant_npos = static_cast<size_t>(-1);
constexpr unsigned int __variant_npos = static_cast<unsigned int>(-1);
namespace __find_detail {
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr size_t __find_index() {
constexpr bool __matches[] = {is_same_v<_Tp, _Types>...};
size_t __result = __not_found;
for (size_t __i = 0; __i < sizeof...(_Types); ++__i) {
if (__matches[__i]) {
if (__result != __not_found) {
return __ambiguous;
}
__result = __i;
}
}
return __result;
}
template <size_t _Index>
struct __find_unambiguous_index_sfinae_impl
: integral_constant<size_t, _Index> {};
template <>
struct __find_unambiguous_index_sfinae_impl<__not_found> {};
template <>
struct __find_unambiguous_index_sfinae_impl<__ambiguous> {};
template <class _Tp, class... _Types>
struct __find_unambiguous_index_sfinae
: __find_unambiguous_index_sfinae_impl<__find_index<_Tp, _Types...>()> {};
} // namespace __find_detail
namespace __variant_detail {
struct __valueless_t {};
enum class _Trait { _TriviallyAvailable, _Available, _Unavailable };
template <typename _Tp,
template <typename> class _IsTriviallyAvailable,
template <typename> class _IsAvailable>
constexpr _Trait __trait =
_IsTriviallyAvailable<_Tp>::value
? _Trait::_TriviallyAvailable
: _IsAvailable<_Tp>::value ? _Trait::_Available : _Trait::_Unavailable;
inline _LIBCPP_INLINE_VISIBILITY
constexpr _Trait __common_trait(initializer_list<_Trait> __traits) {
_Trait __result = _Trait::_TriviallyAvailable;
for (_Trait __t : __traits) {
if (static_cast<int>(__t) > static_cast<int>(__result)) {
__result = __t;
}
}
return __result;
}
template <typename... _Types>
struct __traits {
static constexpr _Trait __copy_constructible_trait =
__common_trait({__trait<_Types,
is_trivially_copy_constructible,
is_copy_constructible>...});
static constexpr _Trait __move_constructible_trait =
__common_trait({__trait<_Types,
is_trivially_move_constructible,
is_move_constructible>...});
static constexpr _Trait __copy_assignable_trait = __common_trait(
{__copy_constructible_trait,
__trait<_Types, is_trivially_copy_assignable, is_copy_assignable>...});
static constexpr _Trait __move_assignable_trait = __common_trait(
{__move_constructible_trait,
__trait<_Types, is_trivially_move_assignable, is_move_assignable>...});
static constexpr _Trait __destructible_trait = __common_trait(
{__trait<_Types, is_trivially_destructible, is_destructible>...});
};
namespace __access {
struct __union {
template <class _Vp>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto&& __get_alt(_Vp&& __v, in_place_index_t<0>) {
return _VSTD::forward<_Vp>(__v).__head;
}
template <class _Vp, size_t _Ip>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto&& __get_alt(_Vp&& __v, in_place_index_t<_Ip>) {
return __get_alt(_VSTD::forward<_Vp>(__v).__tail, in_place_index<_Ip - 1>);
}
};
struct __base {
template <size_t _Ip, class _Vp>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto&& __get_alt(_Vp&& __v) {
return __union::__get_alt(_VSTD::forward<_Vp>(__v).__data,
in_place_index<_Ip>);
}
};
struct __variant {
template <size_t _Ip, class _Vp>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto&& __get_alt(_Vp&& __v) {
return __base::__get_alt<_Ip>(_VSTD::forward<_Vp>(__v).__impl);
}
};
} // namespace __access
namespace __visitation {
struct __base {
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto)
__visit_alt_at(size_t __index, _Visitor&& __visitor, _Vs&&... __vs) {
constexpr auto __fdiagonal =
__make_fdiagonal<_Visitor&&,
decltype(_VSTD::forward<_Vs>(__vs).__as_base())...>();
return __fdiagonal[__index](_VSTD::forward<_Visitor>(__visitor),
_VSTD::forward<_Vs>(__vs).__as_base()...);
}
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto) __visit_alt(_Visitor&& __visitor,
_Vs&&... __vs) {
constexpr auto __fmatrix =
__make_fmatrix<_Visitor&&,
decltype(_VSTD::forward<_Vs>(__vs).__as_base())...>();
return __at(__fmatrix, __vs.index()...)(
_VSTD::forward<_Visitor>(__visitor),
_VSTD::forward<_Vs>(__vs).__as_base()...);
}
private:
template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr const _Tp& __at(const _Tp& __elem) { return __elem; }
template <class _Tp, size_t _Np, typename... _Indices>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto&& __at(const array<_Tp, _Np>& __elems,
size_t __index, _Indices... __indices) {
return __at(__elems[__index], __indices...);
}
template <class _Fp, class... _Fs>
static constexpr void __std_visit_visitor_return_type_check() {
static_assert(
__all<is_same_v<_Fp, _Fs>...>::value,
"`std::visit` requires the visitor to have a single return type.");
}
template <class... _Fs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_farray(_Fs&&... __fs) {
__std_visit_visitor_return_type_check<decay_t<_Fs>...>();
using __result = array<common_type_t<decay_t<_Fs>...>, sizeof...(_Fs)>;
return __result{{_VSTD::forward<_Fs>(__fs)...}};
}
template <std::size_t... _Is>
struct __dispatcher {
template <class _Fp, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto) __dispatch(_Fp __f, _Vs... __vs) {
return __invoke_constexpr(
static_cast<_Fp>(__f),
__access::__base::__get_alt<_Is>(static_cast<_Vs>(__vs))...);
}
};
template <class _Fp, class... _Vs, size_t... _Is>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_dispatch(index_sequence<_Is...>) {
return __dispatcher<_Is...>::template __dispatch<_Fp, _Vs...>;
}
template <size_t _Ip, class _Fp, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_fdiagonal_impl() {
return __make_dispatch<_Fp, _Vs...>(
index_sequence<(__identity<_Vs>{}, _Ip)...>{});
}
template <class _Fp, class... _Vs, size_t... _Is>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_fdiagonal_impl(index_sequence<_Is...>) {
return __base::__make_farray(__make_fdiagonal_impl<_Is, _Fp, _Vs...>()...);
}
template <class _Fp, class _Vp, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_fdiagonal() {
constexpr size_t _Np = decay_t<_Vp>::__size();
static_assert(__all<(_Np == decay_t<_Vs>::__size())...>::value);
return __make_fdiagonal_impl<_Fp, _Vp, _Vs...>(make_index_sequence<_Np>{});
}
template <class _Fp, class... _Vs, size_t... _Is>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_fmatrix_impl(index_sequence<_Is...> __is) {
return __make_dispatch<_Fp, _Vs...>(__is);
}
template <class _Fp, class... _Vs, size_t... _Is, size_t... _Js, class... _Ls>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_fmatrix_impl(index_sequence<_Is...>,
index_sequence<_Js...>,
_Ls... __ls) {
return __base::__make_farray(__make_fmatrix_impl<_Fp, _Vs...>(
index_sequence<_Is..., _Js>{}, __ls...)...);
}
template <class _Fp, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_fmatrix() {
return __make_fmatrix_impl<_Fp, _Vs...>(
index_sequence<>{}, make_index_sequence<decay_t<_Vs>::__size()>{}...);
}
};
struct __variant {
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto)
__visit_alt_at(size_t __index, _Visitor&& __visitor, _Vs&&... __vs) {
return __base::__visit_alt_at(__index,
_VSTD::forward<_Visitor>(__visitor),
_VSTD::forward<_Vs>(__vs).__impl...);
}
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto) __visit_alt(_Visitor&& __visitor,
_Vs&&... __vs) {
return __base::__visit_alt(_VSTD::forward<_Visitor>(__visitor),
_VSTD::forward<_Vs>(__vs).__impl...);
}
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto)
__visit_value_at(size_t __index, _Visitor&& __visitor, _Vs&&... __vs) {
return __visit_alt_at(
__index,
__make_value_visitor(_VSTD::forward<_Visitor>(__visitor)),
_VSTD::forward<_Vs>(__vs)...);
}
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr decltype(auto) __visit_value(_Visitor&& __visitor,
_Vs&&... __vs) {
return __visit_alt(
__make_value_visitor(_VSTD::forward<_Visitor>(__visitor)),
_VSTD::forward<_Vs>(__vs)...);
}
private:
template <class _Visitor, class... _Values>
static constexpr void __std_visit_exhaustive_visitor_check() {
static_assert(is_callable_v<_Visitor(_Values...)>,
"`std::visit` requires the visitor to be exhaustive.");
}
template <class _Visitor>
struct __value_visitor {
template <class... _Alts>
inline _LIBCPP_INLINE_VISIBILITY
constexpr decltype(auto) operator()(_Alts&&... __alts) const {
__std_visit_exhaustive_visitor_check<
_Visitor,
decltype((_VSTD::forward<_Alts>(__alts).__value))...>();
return __invoke_constexpr(_VSTD::forward<_Visitor>(__visitor),
_VSTD::forward<_Alts>(__alts).__value...);
}
_Visitor&& __visitor;
};
template <class _Visitor>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto __make_value_visitor(_Visitor&& __visitor) {
return __value_visitor<_Visitor>{_VSTD::forward<_Visitor>(__visitor)};
}
};
} // namespace __visitation
template <size_t _Index, class _Tp>
struct _LIBCPP_TEMPLATE_VIS __alt {
using __value_type = _Tp;
template <class... _Args>
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr __alt(in_place_t, _Args&&... __args)
: __value(_VSTD::forward<_Args>(__args)...) {}
__value_type __value;
};
template <_Trait _DestructibleTrait, size_t _Index, class... _Types>
union _LIBCPP_TEMPLATE_VIS __union;
template <_Trait _DestructibleTrait, size_t _Index>
union _LIBCPP_TEMPLATE_VIS __union<_DestructibleTrait, _Index> {};
#define _LIBCPP_VARIANT_UNION(destructible_trait, destructor) \
template <size_t _Index, class _Tp, class... _Types> \
union _LIBCPP_TEMPLATE_VIS __union<destructible_trait, \
_Index, \
_Tp, \
_Types...> { \
public: \
inline _LIBCPP_INLINE_VISIBILITY \
explicit constexpr __union(__valueless_t) noexcept : __dummy{} {} \
\
template <class... _Args> \
inline _LIBCPP_INLINE_VISIBILITY \
explicit constexpr __union(in_place_index_t<0>, _Args&&... __args) \
: __head(in_place, _VSTD::forward<_Args>(__args)...) {} \
\
template <size_t _Ip, class... _Args> \
inline _LIBCPP_INLINE_VISIBILITY \
explicit constexpr __union(in_place_index_t<_Ip>, _Args&&... __args) \
: __tail(in_place_index<_Ip - 1>, _VSTD::forward<_Args>(__args)...) {} \
\
__union(const __union&) = default; \
__union(__union&&) = default; \
\
destructor \
\
__union& operator=(const __union&) = default; \
__union& operator=(__union&&) = default; \
\
private: \
char __dummy; \
__alt<_Index, _Tp> __head; \
__union<destructible_trait, _Index + 1, _Types...> __tail; \
\
friend struct __access::__union; \
}
_LIBCPP_VARIANT_UNION(_Trait::_TriviallyAvailable, ~__union() = default;);
_LIBCPP_VARIANT_UNION(_Trait::_Available, ~__union() {});
_LIBCPP_VARIANT_UNION(_Trait::_Unavailable, ~__union() = delete;);
#undef _LIBCPP_VARIANT_UNION
template <_Trait _DestructibleTrait, class... _Types>
class _LIBCPP_TEMPLATE_VIS __base {
public:
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr __base(__valueless_t tag) noexcept
: __data(tag), __index(__variant_npos) {}
template <size_t _Ip, class... _Args>
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr __base(in_place_index_t<_Ip>, _Args&&... __args)
:
__data(in_place_index<_Ip>, _VSTD::forward<_Args>(__args)...),
__index(_Ip) {}
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool valueless_by_exception() const noexcept {
return index() == variant_npos;
}
inline _LIBCPP_INLINE_VISIBILITY
constexpr size_t index() const noexcept {
return __index == __variant_npos ? variant_npos : __index;
}
protected:
inline _LIBCPP_INLINE_VISIBILITY
constexpr auto&& __as_base() & { return *this; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr auto&& __as_base() && { return _VSTD::move(*this); }
inline _LIBCPP_INLINE_VISIBILITY
constexpr auto&& __as_base() const & { return *this; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr auto&& __as_base() const && { return _VSTD::move(*this); }
inline _LIBCPP_INLINE_VISIBILITY
static constexpr size_t __size() { return sizeof...(_Types); }
__union<_DestructibleTrait, 0, _Types...> __data;
unsigned int __index;
friend struct __access::__base;
friend struct __visitation::__base;
};
template <class _Traits, _Trait = _Traits::__destructible_trait>
class _LIBCPP_TEMPLATE_VIS __destructor;
#define _LIBCPP_VARIANT_DESTRUCTOR(destructible_trait, destructor, destroy) \
template <class... _Types> \
class _LIBCPP_TEMPLATE_VIS __destructor<__traits<_Types...>, \
destructible_trait> \
: public __base<destructible_trait, _Types...> { \
using __base_type = __base<destructible_trait, _Types...>; \
\
public: \
using __base_type::__base_type; \
using __base_type::operator=; \
\
__destructor(const __destructor&) = default; \
__destructor(__destructor&&) = default; \
destructor \
__destructor& operator=(const __destructor&) = default; \
__destructor& operator=(__destructor&&) = default; \
\
protected: \
inline _LIBCPP_INLINE_VISIBILITY \
destroy \
}
_LIBCPP_VARIANT_DESTRUCTOR(
_Trait::_TriviallyAvailable,
~__destructor() = default;,
void __destroy() noexcept { this->__index = __variant_npos; });
_LIBCPP_VARIANT_DESTRUCTOR(
_Trait::_Available,
~__destructor() { __destroy(); },
void __destroy() noexcept {
if (!this->valueless_by_exception()) {
__visitation::__base::__visit_alt(
[](auto& __alt) noexcept {
using __alt_type = decay_t<decltype(__alt)>;
__alt.~__alt_type();
},
*this);
}
this->__index = __variant_npos;
});
_LIBCPP_VARIANT_DESTRUCTOR(
_Trait::_Unavailable,
~__destructor() = delete;,
void __destroy() noexcept = delete;);
#undef _LIBCPP_VARIANT_DESTRUCTOR
template <class _Traits>
class _LIBCPP_TEMPLATE_VIS __constructor : public __destructor<_Traits> {
using __base_type = __destructor<_Traits>;
public:
using __base_type::__base_type;
using __base_type::operator=;
protected:
template <size_t _Ip, class _Tp, class... _Args>
inline _LIBCPP_INLINE_VISIBILITY
static _Tp& __construct_alt(__alt<_Ip, _Tp>& __a, _Args&&... __args) {
::new ((void*)_VSTD::addressof(__a))
__alt<_Ip, _Tp>(in_place, _VSTD::forward<_Args>(__args)...);
return __a.__value;
}
template <class _Rhs>
inline _LIBCPP_INLINE_VISIBILITY
static void __generic_construct(__constructor& __lhs, _Rhs&& __rhs) {
__lhs.__destroy();
if (!__rhs.valueless_by_exception()) {
__visitation::__base::__visit_alt_at(
__rhs.index(),
[](auto& __lhs_alt, auto&& __rhs_alt) {
__construct_alt(
__lhs_alt,
_VSTD::forward<decltype(__rhs_alt)>(__rhs_alt).__value);
},
__lhs, _VSTD::forward<_Rhs>(__rhs));
__lhs.__index = __rhs.index();
}
}
};
template <class _Traits, _Trait = _Traits::__move_constructible_trait>
class _LIBCPP_TEMPLATE_VIS __move_constructor;
#define _LIBCPP_VARIANT_MOVE_CONSTRUCTOR(move_constructible_trait, \
move_constructor) \
template <class... _Types> \
class _LIBCPP_TEMPLATE_VIS __move_constructor<__traits<_Types...>, \
move_constructible_trait> \
: public __constructor<__traits<_Types...>> { \
using __base_type = __constructor<__traits<_Types...>>; \
\
public: \
using __base_type::__base_type; \
using __base_type::operator=; \
\
__move_constructor(const __move_constructor&) = default; \
move_constructor \
~__move_constructor() = default; \
__move_constructor& operator=(const __move_constructor&) = default; \
__move_constructor& operator=(__move_constructor&&) = default; \
}
_LIBCPP_VARIANT_MOVE_CONSTRUCTOR(
_Trait::_TriviallyAvailable,
__move_constructor(__move_constructor&& __that) = default;);
_LIBCPP_VARIANT_MOVE_CONSTRUCTOR(
_Trait::_Available,
__move_constructor(__move_constructor&& __that) noexcept(
__all<is_nothrow_move_constructible_v<_Types>...>::value)
: __move_constructor(__valueless_t{}) {
this->__generic_construct(*this, _VSTD::move(__that));
});
_LIBCPP_VARIANT_MOVE_CONSTRUCTOR(
_Trait::_Unavailable,
__move_constructor(__move_constructor&&) = delete;);
#undef _LIBCPP_VARIANT_MOVE_CONSTRUCTOR
template <class _Traits, _Trait = _Traits::__copy_constructible_trait>
class _LIBCPP_TEMPLATE_VIS __copy_constructor;
#define _LIBCPP_VARIANT_COPY_CONSTRUCTOR(copy_constructible_trait, \
copy_constructor) \
template <class... _Types> \
class _LIBCPP_TEMPLATE_VIS __copy_constructor<__traits<_Types...>, \
copy_constructible_trait> \
: public __move_constructor<__traits<_Types...>> { \
using __base_type = __move_constructor<__traits<_Types...>>; \
\
public: \
using __base_type::__base_type; \
using __base_type::operator=; \
\
copy_constructor \
__copy_constructor(__copy_constructor&&) = default; \
~__copy_constructor() = default; \
__copy_constructor& operator=(const __copy_constructor&) = default; \
__copy_constructor& operator=(__copy_constructor&&) = default; \
}
_LIBCPP_VARIANT_COPY_CONSTRUCTOR(
_Trait::_TriviallyAvailable,
__copy_constructor(const __copy_constructor& __that) = default;);
_LIBCPP_VARIANT_COPY_CONSTRUCTOR(
_Trait::_Available,
__copy_constructor(const __copy_constructor& __that)
: __copy_constructor(__valueless_t{}) {
this->__generic_construct(*this, __that);
});
_LIBCPP_VARIANT_COPY_CONSTRUCTOR(
_Trait::_Unavailable,
__copy_constructor(const __copy_constructor&) = delete;);
#undef _LIBCPP_VARIANT_COPY_CONSTRUCTOR
template <class _Traits>
class _LIBCPP_TEMPLATE_VIS __assignment : public __copy_constructor<_Traits> {
using __base_type = __copy_constructor<_Traits>;
public:
using __base_type::__base_type;
using __base_type::operator=;
template <size_t _Ip, class... _Args>
inline _LIBCPP_INLINE_VISIBILITY
auto& __emplace(_Args&&... __args) {
this->__destroy();
auto& __res = this->__construct_alt(__access::__base::__get_alt<_Ip>(*this),
_VSTD::forward<_Args>(__args)...);
this->__index = _Ip;
return __res;
}
protected:
template <size_t _Ip, class _Tp, class _Arg>
inline _LIBCPP_INLINE_VISIBILITY
void __assign_alt(__alt<_Ip, _Tp>& __a, _Arg&& __arg) {
if (this->index() == _Ip) {
__a.__value = _VSTD::forward<_Arg>(__arg);
} else {
struct {
void operator()(true_type) const {
__this->__emplace<_Ip>(_VSTD::forward<_Arg>(__arg));
}
void operator()(false_type) const {
__this->__emplace<_Ip>(_Tp(_VSTD::forward<_Arg>(__arg)));
}
__assignment* __this;
_Arg&& __arg;
} __impl{this, _VSTD::forward<_Arg>(__arg)};
__impl(bool_constant<is_nothrow_constructible_v<_Tp, _Arg> ||
!is_nothrow_move_constructible_v<_Tp>>{});
}
}
template <class _That>
inline _LIBCPP_INLINE_VISIBILITY
void __generic_assign(_That&& __that) {
if (this->valueless_by_exception() && __that.valueless_by_exception()) {
// do nothing.
} else if (__that.valueless_by_exception()) {
this->__destroy();
} else {
__visitation::__base::__visit_alt_at(
__that.index(),
[this](auto& __this_alt, auto&& __that_alt) {
this->__assign_alt(
__this_alt,
_VSTD::forward<decltype(__that_alt)>(__that_alt).__value);
},
*this, _VSTD::forward<_That>(__that));
}
}
};
template <class _Traits, _Trait = _Traits::__move_assignable_trait>
class _LIBCPP_TEMPLATE_VIS __move_assignment;
#define _LIBCPP_VARIANT_MOVE_ASSIGNMENT(move_assignable_trait, \
move_assignment) \
template <class... _Types> \
class _LIBCPP_TEMPLATE_VIS __move_assignment<__traits<_Types...>, \
move_assignable_trait> \
: public __assignment<__traits<_Types...>> { \
using __base_type = __assignment<__traits<_Types...>>; \
\
public: \
using __base_type::__base_type; \
using __base_type::operator=; \
\
__move_assignment(const __move_assignment&) = default; \
__move_assignment(__move_assignment&&) = default; \
~__move_assignment() = default; \
__move_assignment& operator=(const __move_assignment&) = default; \
move_assignment \
}
_LIBCPP_VARIANT_MOVE_ASSIGNMENT(
_Trait::_TriviallyAvailable,
__move_assignment& operator=(__move_assignment&& __that) = default;);
_LIBCPP_VARIANT_MOVE_ASSIGNMENT(
_Trait::_Available,
__move_assignment& operator=(__move_assignment&& __that) noexcept(
__all<(is_nothrow_move_constructible_v<_Types> &&
is_nothrow_move_assignable_v<_Types>)...>::value) {
this->__generic_assign(_VSTD::move(__that));
return *this;
});
_LIBCPP_VARIANT_MOVE_ASSIGNMENT(
_Trait::_Unavailable,
__move_assignment& operator=(__move_assignment&&) = delete;);
#undef _LIBCPP_VARIANT_MOVE_ASSIGNMENT
template <class _Traits, _Trait = _Traits::__copy_assignable_trait>
class _LIBCPP_TEMPLATE_VIS __copy_assignment;
#define _LIBCPP_VARIANT_COPY_ASSIGNMENT(copy_assignable_trait, \
copy_assignment) \
template <class... _Types> \
class _LIBCPP_TEMPLATE_VIS __copy_assignment<__traits<_Types...>, \
copy_assignable_trait> \
: public __move_assignment<__traits<_Types...>> { \
using __base_type = __move_assignment<__traits<_Types...>>; \
\
public: \
using __base_type::__base_type; \
using __base_type::operator=; \
\
__copy_assignment(const __copy_assignment&) = default; \
__copy_assignment(__copy_assignment&&) = default; \
~__copy_assignment() = default; \
copy_assignment \
__copy_assignment& operator=(__copy_assignment&&) = default; \
}
_LIBCPP_VARIANT_COPY_ASSIGNMENT(
_Trait::_TriviallyAvailable,
__copy_assignment& operator=(const __copy_assignment& __that) = default;);
_LIBCPP_VARIANT_COPY_ASSIGNMENT(
_Trait::_Available,
__copy_assignment& operator=(const __copy_assignment& __that) {
this->__generic_assign(__that);
return *this;
});
_LIBCPP_VARIANT_COPY_ASSIGNMENT(
_Trait::_Unavailable,
__copy_assignment& operator=(const __copy_assignment&) = delete;);
#undef _LIBCPP_VARIANT_COPY_ASSIGNMENT
template <class... _Types>
class _LIBCPP_TEMPLATE_VIS __impl
: public __copy_assignment<__traits<_Types...>> {
using __base_type = __copy_assignment<__traits<_Types...>>;
public:
using __base_type::__base_type;
using __base_type::operator=;
template <size_t _Ip, class _Arg>
inline _LIBCPP_INLINE_VISIBILITY
void __assign(_Arg&& __arg) {
this->__assign_alt(__access::__base::__get_alt<_Ip>(*this),
_VSTD::forward<_Arg>(__arg));
}
inline _LIBCPP_INLINE_VISIBILITY
void __swap(__impl& __that) {
if (this->valueless_by_exception() && __that.valueless_by_exception()) {
// do nothing.
} else if (this->index() == __that.index()) {
__visitation::__base::__visit_alt_at(
this->index(),
[](auto& __this_alt, auto& __that_alt) {
using _VSTD::swap;
swap(__this_alt.__value, __that_alt.__value);
},
*this,
__that);
} else {
__impl* __lhs = this;
__impl* __rhs = _VSTD::addressof(__that);
if (__lhs->__move_nothrow() && !__rhs->__move_nothrow()) {
_VSTD::swap(__lhs, __rhs);
}
__impl __tmp(_VSTD::move(*__rhs));
#ifndef _LIBCPP_NO_EXCEPTIONS
// EXTENSION: When the move construction of `__lhs` into `__rhs` throws
// and `__tmp` is nothrow move constructible then we move `__tmp` back
// into `__rhs` and provide the strong exception safety guarentee.
try {
this->__generic_construct(*__rhs, _VSTD::move(*__lhs));
} catch (...) {
if (__tmp.__move_nothrow()) {
this->__generic_construct(*__rhs, _VSTD::move(__tmp));
}
throw;
}
#else
this->__generic_construct(*__rhs, _VSTD::move(*__lhs));
#endif
this->__generic_construct(*__lhs, _VSTD::move(__tmp));
}
}
private:
inline _LIBCPP_INLINE_VISIBILITY
bool __move_nothrow() const {
constexpr bool __results[] = {is_nothrow_move_constructible_v<_Types>...};
return this->valueless_by_exception() || __results[this->index()];
}
};
template <class... _Types>
struct __overload;
template <>
struct __overload<> { void operator()() const; };
template <class _Tp, class... _Types>
struct __overload<_Tp, _Types...> : __overload<_Types...> {
using __overload<_Types...>::operator();
__identity<_Tp> operator()(_Tp) const;
};
template <class _Tp, class... _Types>
using __best_match_t = typename result_of_t<__overload<_Types...>(_Tp&&)>::type;
} // __variant_detail
template <class... _Types>
class _LIBCPP_TEMPLATE_VIS variant
: private __sfinae_ctor_base<
__all<is_copy_constructible_v<_Types>...>::value,
__all<is_move_constructible_v<_Types>...>::value>,
private __sfinae_assign_base<
__all<(is_copy_constructible_v<_Types> &&
is_copy_assignable_v<_Types>)...>::value,
__all<(is_move_constructible_v<_Types> &&
is_move_assignable_v<_Types>)...>::value> {
static_assert(0 < sizeof...(_Types),
"variant must consist of at least one alternative.");
static_assert(__all<!is_array_v<_Types>...>::value,
"variant can not have an array type as an alternative.");
static_assert(__all<!is_reference_v<_Types>...>::value,
"variant can not have a reference type as an alternative.");
static_assert(__all<!is_void_v<_Types>...>::value,
"variant can not have a void type as an alternative.");
using __first_type = variant_alternative_t<0, variant>;
public:
template <bool _Dummy = true,
enable_if_t<__dependent_type<is_default_constructible<__first_type>,
_Dummy>::value,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
constexpr variant() noexcept(is_nothrow_default_constructible_v<__first_type>)
: __impl(in_place_index<0>) {}
variant(const variant&) = default;
variant(variant&&) = default;
template <
class _Arg,
enable_if_t<!is_same_v<decay_t<_Arg>, variant>, int> = 0,
enable_if_t<!__is_inplace_type<decay_t<_Arg>>::value, int> = 0,
enable_if_t<!__is_inplace_index<decay_t<_Arg>>::value, int> = 0,
class _Tp = __variant_detail::__best_match_t<_Arg, _Types...>,
size_t _Ip =
__find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
enable_if_t<is_constructible_v<_Tp, _Arg>, int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
constexpr variant(_Arg&& __arg) noexcept(
is_nothrow_constructible_v<_Tp, _Arg>)
: __impl(in_place_index<_Ip>, _VSTD::forward<_Arg>(__arg)) {}
template <size_t _Ip, class... _Args,
class = enable_if_t<(_Ip < sizeof...(_Types)), int>,
class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr variant(
in_place_index_t<_Ip>,
_Args&&... __args) noexcept(is_nothrow_constructible_v<_Tp, _Args...>)
: __impl(in_place_index<_Ip>, _VSTD::forward<_Args>(__args)...) {}
template <
size_t _Ip,
class _Up,
class... _Args,
enable_if_t<(_Ip < sizeof...(_Types)), int> = 0,
class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr variant(
in_place_index_t<_Ip>,
initializer_list<_Up> __il,
_Args&&... __args) noexcept(
is_nothrow_constructible_v<_Tp, initializer_list<_Up>&, _Args...>)
: __impl(in_place_index<_Ip>, __il, _VSTD::forward<_Args>(__args)...) {}
template <
class _Tp,
class... _Args,
size_t _Ip =
__find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr variant(in_place_type_t<_Tp>, _Args&&... __args) noexcept(
is_nothrow_constructible_v<_Tp, _Args...>)
: __impl(in_place_index<_Ip>, _VSTD::forward<_Args>(__args)...) {}
template <
class _Tp,
class _Up,
class... _Args,
size_t _Ip =
__find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
explicit constexpr variant(
in_place_type_t<_Tp>,
initializer_list<_Up> __il,
_Args&&... __args) noexcept(
is_nothrow_constructible_v<_Tp, initializer_list< _Up>&, _Args...>)
: __impl(in_place_index<_Ip>, __il, _VSTD::forward<_Args>(__args)...) {}
~variant() = default;
variant& operator=(const variant&) = default;
variant& operator=(variant&&) = default;
template <
class _Arg,
enable_if_t<!is_same_v<decay_t<_Arg>, variant>, int> = 0,
class _Tp = __variant_detail::__best_match_t<_Arg, _Types...>,
size_t _Ip =
__find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
enable_if_t<is_assignable_v<_Tp&, _Arg> && is_constructible_v<_Tp, _Arg>,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
variant& operator=(_Arg&& __arg) noexcept(
is_nothrow_assignable_v<_Tp&, _Arg> &&
is_nothrow_constructible_v<_Tp, _Arg>) {
__impl.template __assign<_Ip>(_VSTD::forward<_Arg>(__arg));
return *this;
}
template <
size_t _Ip,
class... _Args,
enable_if_t<(_Ip < sizeof...(_Types)), int> = 0,
class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
_Tp& emplace(_Args&&... __args) {
return __impl.template __emplace<_Ip>(_VSTD::forward<_Args>(__args)...);
}
template <
size_t _Ip,
class _Up,
class... _Args,
enable_if_t<(_Ip < sizeof...(_Types)), int> = 0,
class _Tp = variant_alternative_t<_Ip, variant<_Types...>>,
enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
_Tp& emplace(initializer_list<_Up> __il, _Args&&... __args) {
return __impl.template __emplace<_Ip>(__il, _VSTD::forward<_Args>(__args)...);
}
template <
class _Tp,
class... _Args,
size_t _Ip =
__find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
enable_if_t<is_constructible_v<_Tp, _Args...>, int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
_Tp& emplace(_Args&&... __args) {
return __impl.template __emplace<_Ip>(_VSTD::forward<_Args>(__args)...);
}
template <
class _Tp,
class _Up,
class... _Args,
size_t _Ip =
__find_detail::__find_unambiguous_index_sfinae<_Tp, _Types...>::value,
enable_if_t<is_constructible_v<_Tp, initializer_list<_Up>&, _Args...>,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
_Tp& emplace(initializer_list<_Up> __il, _Args&&... __args) {
return __impl.template __emplace<_Ip>(__il, _VSTD::forward<_Args>(__args)...);
}
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool valueless_by_exception() const noexcept {
return __impl.valueless_by_exception();
}
inline _LIBCPP_INLINE_VISIBILITY
constexpr size_t index() const noexcept { return __impl.index(); }
template <
bool _Dummy = true,
enable_if_t<
__all<(
__dependent_type<is_move_constructible<_Types>, _Dummy>::value &&
__dependent_type<is_swappable<_Types>, _Dummy>::value)...>::value,
int> = 0>
inline _LIBCPP_INLINE_VISIBILITY
void swap(variant& __that) noexcept(
__all<(is_nothrow_move_constructible_v<_Types> &&
is_nothrow_swappable_v<_Types>)...>::value) {
__impl.__swap(__that.__impl);
}
private:
__variant_detail::__impl<_Types...> __impl;
friend struct __variant_detail::__access::__variant;
friend struct __variant_detail::__visitation::__variant;
};
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool __holds_alternative(const variant<_Types...>& __v) noexcept {
return __v.index() == _Ip;
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool holds_alternative(const variant<_Types...>& __v) noexcept {
return __holds_alternative<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
}
template <size_t _Ip, class _Vp>
inline _LIBCPP_INLINE_VISIBILITY
static constexpr auto&& __generic_get(_Vp&& __v) {
using __variant_detail::__access::__variant;
if (!__holds_alternative<_Ip>(__v)) {
__throw_bad_variant_access();
}
return __variant::__get_alt<_Ip>(_VSTD::forward<_Vp>(__v)).__value;
}
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr variant_alternative_t<_Ip, variant<_Types...>>& get(
variant<_Types...>& __v) {
static_assert(_Ip < sizeof...(_Types));
static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
return __generic_get<_Ip>(__v);
}
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr variant_alternative_t<_Ip, variant<_Types...>>&& get(
variant<_Types...>&& __v) {
static_assert(_Ip < sizeof...(_Types));
static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
return __generic_get<_Ip>(_VSTD::move(__v));
}
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr const variant_alternative_t<_Ip, variant<_Types...>>& get(
const variant<_Types...>& __v) {
static_assert(_Ip < sizeof...(_Types));
static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
return __generic_get<_Ip>(__v);
}
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr const variant_alternative_t<_Ip, variant<_Types...>>&& get(
const variant<_Types...>&& __v) {
static_assert(_Ip < sizeof...(_Types));
static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
return __generic_get<_Ip>(_VSTD::move(__v));
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr _Tp& get(variant<_Types...>& __v) {
static_assert(!is_void_v<_Tp>);
return _VSTD::get<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr _Tp&& get(variant<_Types...>&& __v) {
static_assert(!is_void_v<_Tp>);
return _VSTD::get<__find_exactly_one_t<_Tp, _Types...>::value>(
_VSTD::move(__v));
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr const _Tp& get(const variant<_Types...>& __v) {
static_assert(!is_void_v<_Tp>);
return _VSTD::get<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr const _Tp&& get(const variant<_Types...>&& __v) {
static_assert(!is_void_v<_Tp>);
return _VSTD::get<__find_exactly_one_t<_Tp, _Types...>::value>(
_VSTD::move(__v));
}
template <size_t _Ip, class _Vp>
inline _LIBCPP_INLINE_VISIBILITY
constexpr auto* __generic_get_if(_Vp* __v) noexcept {
using __variant_detail::__access::__variant;
return __v && __holds_alternative<_Ip>(*__v)
? _VSTD::addressof(__variant::__get_alt<_Ip>(*__v).__value)
: nullptr;
}
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr add_pointer_t<variant_alternative_t<_Ip, variant<_Types...>>>
get_if(variant<_Types...>* __v) noexcept {
static_assert(_Ip < sizeof...(_Types));
static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
return __generic_get_if<_Ip>(__v);
}
template <size_t _Ip, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr add_pointer_t<const variant_alternative_t<_Ip, variant<_Types...>>>
get_if(const variant<_Types...>* __v) noexcept {
static_assert(_Ip < sizeof...(_Types));
static_assert(!is_void_v<variant_alternative_t<_Ip, variant<_Types...>>>);
return __generic_get_if<_Ip>(__v);
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr add_pointer_t<_Tp>
get_if(variant<_Types...>* __v) noexcept {
static_assert(!is_void_v<_Tp>);
return _VSTD::get_if<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
}
template <class _Tp, class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr add_pointer_t<const _Tp>
get_if(const variant<_Types...>* __v) noexcept {
static_assert(!is_void_v<_Tp>);
return _VSTD::get_if<__find_exactly_one_t<_Tp, _Types...>::value>(__v);
}
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator==(const variant<_Types...>& __lhs,
const variant<_Types...>& __rhs) {
using __variant_detail::__visitation::__variant;
if (__lhs.index() != __rhs.index()) return false;
if (__lhs.valueless_by_exception()) return true;
return __variant::__visit_value_at(__lhs.index(), equal_to<>{}, __lhs, __rhs);
}
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator!=(const variant<_Types...>& __lhs,
const variant<_Types...>& __rhs) {
using __variant_detail::__visitation::__variant;
if (__lhs.index() != __rhs.index()) return true;
if (__lhs.valueless_by_exception()) return false;
return __variant::__visit_value_at(
__lhs.index(), not_equal_to<>{}, __lhs, __rhs);
}
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator<(const variant<_Types...>& __lhs,
const variant<_Types...>& __rhs) {
using __variant_detail::__visitation::__variant;
if (__rhs.valueless_by_exception()) return false;
if (__lhs.valueless_by_exception()) return true;
if (__lhs.index() < __rhs.index()) return true;
if (__lhs.index() > __rhs.index()) return false;
return __variant::__visit_value_at(__lhs.index(), less<>{}, __lhs, __rhs);
}
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator>(const variant<_Types...>& __lhs,
const variant<_Types...>& __rhs) {
using __variant_detail::__visitation::__variant;
if (__lhs.valueless_by_exception()) return false;
if (__rhs.valueless_by_exception()) return true;
if (__lhs.index() > __rhs.index()) return true;
if (__lhs.index() < __rhs.index()) return false;
return __variant::__visit_value_at(__lhs.index(), greater<>{}, __lhs, __rhs);
}
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator<=(const variant<_Types...>& __lhs,
const variant<_Types...>& __rhs) {
using __variant_detail::__visitation::__variant;
if (__lhs.valueless_by_exception()) return true;
if (__rhs.valueless_by_exception()) return false;
if (__lhs.index() < __rhs.index()) return true;
if (__lhs.index() > __rhs.index()) return false;
return __variant::__visit_value_at(
__lhs.index(), less_equal<>{}, __lhs, __rhs);
}
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator>=(const variant<_Types...>& __lhs,
const variant<_Types...>& __rhs) {
using __variant_detail::__visitation::__variant;
if (__rhs.valueless_by_exception()) return true;
if (__lhs.valueless_by_exception()) return false;
if (__lhs.index() > __rhs.index()) return true;
if (__lhs.index() < __rhs.index()) return false;
return __variant::__visit_value_at(
__lhs.index(), greater_equal<>{}, __lhs, __rhs);
}
template <class _Visitor, class... _Vs>
inline _LIBCPP_INLINE_VISIBILITY
constexpr decltype(auto) visit(_Visitor&& __visitor, _Vs&&... __vs) {
using __variant_detail::__visitation::__variant;
bool __results[] = {__vs.valueless_by_exception()...};
for (bool __result : __results) {
if (__result) {
__throw_bad_variant_access();
}
}
return __variant::__visit_value(_VSTD::forward<_Visitor>(__visitor),
_VSTD::forward<_Vs>(__vs)...);
}
struct _LIBCPP_TEMPLATE_VIS monostate {};
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator<(monostate, monostate) noexcept { return false; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator>(monostate, monostate) noexcept { return false; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator<=(monostate, monostate) noexcept { return true; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator>=(monostate, monostate) noexcept { return true; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator==(monostate, monostate) noexcept { return true; }
inline _LIBCPP_INLINE_VISIBILITY
constexpr bool operator!=(monostate, monostate) noexcept { return false; }
template <class... _Types>
inline _LIBCPP_INLINE_VISIBILITY
auto swap(variant<_Types...>& __lhs,
variant<_Types...>& __rhs) noexcept(noexcept(__lhs.swap(__rhs)))
-> decltype(__lhs.swap(__rhs)) {
__lhs.swap(__rhs);
}
template <class... _Types>
struct _LIBCPP_TEMPLATE_VIS hash<
__enable_hash_helper<variant<_Types...>, remove_const_t<_Types>...>> {
using argument_type = variant<_Types...>;
using result_type = size_t;
inline _LIBCPP_INLINE_VISIBILITY
result_type operator()(const argument_type& __v) const {
using __variant_detail::__visitation::__variant;
size_t __res =
__v.valueless_by_exception()
? 299792458 // Random value chosen by the universe upon creation
: __variant::__visit_alt(
[](const auto& __alt) {
using __alt_type = decay_t<decltype(__alt)>;
using __value_type = remove_const_t<
typename __alt_type::__value_type>;
return hash<__value_type>{}(__alt.__value);
},
__v);
return __hash_combine(__res, hash<size_t>{}(__v.index()));
}
};
template <>
struct _LIBCPP_TEMPLATE_VIS hash<monostate> {
using argument_type = monostate;
using result_type = size_t;
inline _LIBCPP_INLINE_VISIBILITY
result_type operator()(const argument_type&) const _NOEXCEPT {
return 66740831; // return a fundamentally attractive random value.
}
};
#endif // _LIBCPP_STD_VER > 14
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_VARIANT