Standard library header <any>

This header is part of the general utility library.

Classes

Name	Description
any (C++17)	Objects that hold instances of any CopyConstructible type. (class)
bad_any_cast (C++17)	exception thrown by the value-returning forms of `any_cast` on a type mismatch (class)

Functions

std::swap(std::any) (C++17)	specializes the std::swap algorithm (function)
any_cast (C++17)	type-safe access to the contained object (function template)

Synopsis

namespace std {
  // class bad_any_cast
  class bad_any_cast;
  // class any
  class any;
  // non-member functions
  void swap(any& x, any& y) noexcept;
  template <class T, class... Args>
  any make_any(Args&& ...args);
  template <class T, class U, class... Args>
  any make_any(initializer_list<U> il, Args&& ...args);
  template<class ValueType>
  ValueType any_cast(const any& operand);
  template<class ValueType>
  ValueType any_cast(any& operand);
  template<class ValueType>
  ValueType any_cast(any&& operand);
  template<class ValueType>
  const ValueType* any_cast(const any* operand) noexcept;
  template<class ValueType>
  ValueType* any_cast(any* operand) noexcept;
}

Class std::bad_any_cast

class bad_any_cast : public bad_cast {
public:
  const char* what() const noexcept override;
};

Class std::any

class any {
public:
  // construction and destruction
  constexpr any() noexcept;
  any(const any& other);
  any(any&& other) noexcept;
  template <class ValueType> any(ValueType&& value);
  template <class ValueType, class... Args>
  explicit any(in_place_type_t<ValueType>, Args&&...);
  template <class ValueType, class U, class... Args>
  explicit any(in_place_type_t<ValueType>, initializer_list<U>, Args&&...);
  ~any();
  // assignments
  any& operator=(const any& rhs);
  any& operator=(any&& rhs) noexcept;
  template <class ValueType> any& operator=(ValueType&& rhs);
  // modifiers
  template <class ValueType, class... Args>
  void emplace(Args&& ...);
  template <class ValueType, class U, class... Args>
  void emplace(initializer_list<U>, Args&&...);
  void reset() noexcept;
  void swap(any& rhs) noexcept;
  // observers
  bool has_value() const noexcept;
  const type_info& type() const noexcept;
};

Language
Standard Library Headers
Freestanding and hosted implementations
Named requirements
Language support library
Concepts library (C++20)
Diagnostics library
Utilities library
Strings library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Numerics library
Input/output library
Localizations library
Regular expressions library (C++11)
Atomic operations library (C++11)
Thread support library (C++11)
Filesystem library (C++17)
Technical Specifications