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std::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.

Let U be std::remove_cv_t<std::remove_reference_t<ValueType>>.

1) The program is ill-formed if is_constructible_v<ValueType, const U&> is not true.
2) The program is ill-formed if is_constructible_v<ValueType, U&> is not true.
3) The program is ill-formed if is_constructible_v<ValueType, U> is not true.

Parameters

operand - target any object

Return value

1-2) Returns static_cast<ValueType>(*std::any_cast<U>(&operand))
3) Returns static_cast<ValueType>(std::move(*std::any_cast<U>(&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

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