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C
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assert
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offsetof
operators (delete[])
operators (new[])
operators (std::bitset)
operators (std::bitset)
operators (std::bitset)
operators (std::chrono::duration)
operators (std::chrono::duration)
operators (std::error_condition)
operators (std::function)
operators (std::optional)
operators (std::pair)
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operators (std::tuple)
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std::alignment_of
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std::bad_cast
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std::bad_exception
std::bad_exception::bad_exception
std::bad_exception::what
std::bad_function_call
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std::bad_typeid
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std::begin(std::initializer_list)
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std::bind
std::bind1st
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std::bitset::operators
std::bitset::operator[]
std::bitset::reference
std::bitset::reset
std::bitset::set
std::bitset::size
std::bitset::test
std::bitset::to_string
std::bitset::to_ullong
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std::bit_and
std::bit_and<void>
std::bit_not
std::bit_not<void>
std::bit_or
std::bit_or<void>
std::bit_xor
std::bit_xor<void>
std::boyer_moore_horspool_searcher
std::boyer_moore_searcher
std::byte
std::calloc
std::chars_format
std::chrono::abs(std::chrono::duration)
std::chrono::ceil(std::chrono::duration)
std::chrono::ceil(std::chrono::time_point)
std::chrono::duration
std::chrono::duration::count
std::chrono::duration::duration
std::chrono::duration::max
std::chrono::duration::min
std::chrono::duration::operator-
std::chrono::duration::operator--
std::chrono::duration::operators
std::chrono::duration::operators (%=)
std::chrono::duration::operators (unary)
std::chrono::duration::zero
std::chrono::duration_cast
std::chrono::duration_values
std::chrono::duration_values::max
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std::chrono::floor(std::chrono::duration)
std::chrono::floor(std::chrono::time_point)
std::chrono::high_resolution_clock
std::chrono::high_resolution_clock::now
std::chrono::round(std::chrono::duration)
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std::chrono::steady_clock
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std::chrono::system_clock
std::chrono::system_clock::from_time_t
std::chrono::system_clock::now
std::chrono::system_clock::to_time_t
std::chrono::time_point
std::chrono::time_point::max
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std::chrono::time_point::operators (operator-)
std::chrono::time_point::time_point
std::chrono::time_point::time_since_epoch
std::chrono::time_point_cast
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std::clock
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std::common_type
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std::conditional
std::conjunction
std::const_mem_fun1_ref_t
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std::equal_to
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std::error_code
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std::function
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std::function::swap
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std::getenv
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std::hash
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std::hash(std::shared_ptr)
std::hash::hash
std::hash<std::error_code>
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std::has_unique_object_representations
std::has_virtual_destructor
std::holds_alternative
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std::initializer_list
std::initializer_list::begin
std::initializer_list::end
std::initializer_list::initializer_list
std::initializer_list::size
std::integer_sequence
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std::invalid_argument
std::invoke
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std::in_place
std::in_place_index
std::in_place_index_t
std::in_place_t
std::in_place_type
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std::is_abstract
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std::is_arithmetic
std::is_array
std::is_assignable
std::is_base_of
std::is_bind_expression
std::is_class
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std::is_const
std::is_constructible
std::is_convertible
std::is_copy_assignable
std::is_copy_constructible
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std::is_destructible
std::is_empty
std::is_enum
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std::is_error_code_enum<std::future_errc>
std::is_error_condition_enum
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std::is_final
std::is_floating_point
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std::is_integral
std::is_invocable
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std::is_literal_type
std::is_lvalue_reference
std::is_member_function_pointer
std::is_member_object_pointer
std::is_member_pointer
std::is_move_assignable
std::is_move_constructible
std::is_nothrow_assignable
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std::is_nothrow_copy_assignable
std::is_nothrow_copy_constructible
std::is_nothrow_default_constructible
std::is_nothrow_destructible
std::is_nothrow_invocable
std::is_nothrow_invocable_r
std::is_nothrow_move_assignable
std::is_nothrow_move_constructible
std::is_nothrow_swappable
std::is_nothrow_swappable_with
std::is_null_pointer
std::is_object
std::is_placeholder
std::is_pod
std::is_pointer
std::is_polymorphic
std::is_reference
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std::is_same
std::is_scalar
std::is_signed
std::is_standard_layout
std::is_swappable
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std::is_trivial
std::is_trivially_assignable
std::is_trivially_constructible
std::is_trivially_copyable
std::is_trivially_copy_assignable
std::is_trivially_copy_constructible
std::is_trivially_default_constructible
std::is_trivially_destructible
std::is_trivially_move_assignable
std::is_trivially_move_constructible
std::is_union
std::is_unsigned
std::is_void
std::is_volatile
std::jmp_buf
std::launder
std::length_error
std::less
std::less<void>
std::less_equal
std::less_equal<void>
std::literals::chrono_literals::operator""h
std::literals::chrono_literals::operator""min
std::literals::chrono_literals::operator""ms
std::literals::chrono_literals::operator""ns
std::literals::chrono_literals::operator""s
std::literals::chrono_literals::operator""us
std::localtime
std::logical_and
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std::logical_not
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std::logical_or
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std::logic_error
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std::make_optional
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std::shared_ptr::reset
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std::static_pointer_cast
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std::in_place_t

STD：在[医]位置[医]T型

Defined in header ​​
struct in_place_t {};​(since C++17)

std::in_place_t是一种空类类型，用于消除构造函数和成员函数的重载，其中包含参数%28，可能是用于某些值的就地构造的参数包%29。

另见

in_place in_place_type in_place_index in_place_t in_place_type_t in_place_index_t (C++17)in-place construction tag (class template)
optional (since C++17)a wrapper that may or may not hold an object (class template)

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