std::any_cast

 

C++

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Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)

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initializer_list (C++11)

bitset

hash (C++11)

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rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=

Optional and any

optional (C++17)

any (C++17)

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pair

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piecewise_construct (C++11)

integer_sequence (C++14)

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swap

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move (C++11)

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Type operations

declval (C++11)

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std::any

Member functions

any::any

any::operator=

Modifers

any::clear

any::swap

Observers

any::empty

any::type

Non-member functions

swap(std::any)

any_cast

 

template<class ValueType>     ValueType any_cast(const any& operand);	(1)	(since C++17)
template<class ValueType>     ValueType any_cast(any& operand);	(2)	(since C++17)
template<class ValueType>     ValueType any_cast(any&& operand);	(3)	(since C++17)
template<class ValueType>     const ValueType* any_cast(const any* operand);	(4)	(since C++17)
template<class ValueType>     ValueType* any_cast(any* operand);	(5)	(since C++17)

Performs type-safe access to the contained object.

For (1-3), the program is ill-formed if ValueType is not a reference and std::is_copy_constructible<ValueType>::value is false.

Parameters

operand

-

target any object

Return value

1) Returns *any_cast<std::add_const_t<std::remove_reference_t<ValueType>>>(&operand).

2-3) Returns *any_cast<std::remove_reference_t<ValueType>>(&operand).

4-5) If operand is not a null pointer, and the typeid of the requested ValueType matches that of the contents of operand, a pointer to the value contained by operand, otherwise a null pointer.

Exceptions

1-3) Throws std::bad_any_cast if the typeid of the requested ValueType does not match that of the contents of operand.

4-5)

noexcept specification:  

noexcept