std::experimental::any

C++

Language

Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Algorithms library

Iterators 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

Technical specifications

Filesystem library (filesystem TS)

Library fundamentals (library fundamentals TS)

Library fundamentals 2 (library fundamentals 2 TS)

Extensions for parallelism (parallelism TS)

Extensions for parallelism 2 (parallelism TS v2)

Extensions for concurrency (concurrency TS)

Concepts (concepts TS)

Ranges (ranges TS)

Special mathematical functions (special math TR)

Library fundamentals

experimental::optional

experimental::any

experimental::basic_string_view

experimental::sample

experimental::shared_ptr

experimental::weak_ptr

experimental::apply

experimental::invocation_type experimental::raw_invocation_type

experimental::search

experimental::default_searcher experimental::make_default_searcher

experimental::boyer_moore_searcher experimental::make_boyer_moore_searcher

experimental::boyer_moore_horspool_searcher experimental::make_boyer_moore_horspool_searcher

type-erased and polymorphic allocators

variable templates for type traits

std::experimental::any

Member functions

any::any

any::operator=

Modifers

any::clear

any::swap

Observers

any::empty

any::type

Non-member functions

swap(std::experimental::any)

any_cast

Defined in header <experimental/any>
class any;		(library fundamentals TS)

The class any describes a type-safe container for single values of any type.

1) An object of class any stores an instance of any type that satisfies the constructor requirements or is empty, and this is referred to as the state of the class any object. The stored instance is called the contained object. Two states are equivalent if they are either both empty or if both are not empty and if the contained objects are equivalent.

2) The non-member any_cast functions provide type-safe access to the contained object.

Implementations are encouraged to avoid dynamic allocations for small objects, but such an optimization may only be applied to types that for which std::is_nothrow_move_constructible returns true.

Member functions

(constructor)	constructs an any object (public member function)
operator=	assigns an any object (public member function)
(destructor)	destroys an any object (public member function)
Modifers
clear	destroys contained object (public member function)
swap	swaps two any objects (public member function)
Observers
empty	checks if object holds a value (public member function)
type	returns the typeid of the contained value (public member function)

Non-member functions

swap	swaps two any instances (function)
any_cast	type-safe access to the contained object (function template)

Helper classes

bad_any_cast (library fundamentals TS)

exception thrown by the value-returning forms of any_cast on a type mismatch (class)