C++ standard libraries extensions
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 < cpp | experimental 
 
 
 C++ 
 Feature test macros (C++20)
 Concepts library (C++20)
 Metaprogramming library (C++11)
 Ranges library (C++20)
 Filesystem library (C++17)
 Concurrency support library (C++11)
 Execution control library (C++26)
Experimental 
 Filesystem library (filesystem TS)
 Library fundamentals (library fundamentals TS)
 Library fundamentals 2 (library fundamentals TS v2)
 Library fundamentals 3 (library fundamentals TS v3)
 Extensions for parallelism (parallelism TS)
 Extensions for parallelism 2 (parallelism TS v2)
 Extensions for concurrency (concurrency TS)
 Extensions for concurrency 2 (concurrency TS v2)
 Concepts (concepts TS)
 Ranges (ranges TS)
 Reflection (reflection TS)
 Mathematical special functions (special functions TR)
Library fundamentals
Version 1 of the C++ Extensions for Library Fundamentals, ISO/IEC TS 19568:2015 defines the following new components for the C++ standard library:
Contents
[edit] Not selected for inclusion in C++17
The following components of ISO/IEC TS 19568:2015 were not selected for inclusion in C++17.
[edit] Modified versions of existing classes to support type-erased allocators
Defined in header 
<experimental/functional>  Defined in header 
<experimental/future>  [edit] Memory resource adaptors
[edit] General utilities
Defined in header 
<experimental/utility>  Defined in header 
<experimental/type_traits>   
 deduce the implied function type of the callable object when called with the given argument types 
(class template)
(class template)
[edit] Feature test macros
Defined in header 
<experimental/optional>  __cpp_lib_experimental_optional
(macro constant)
Defined in header 
<experimental/any>  __cpp_lib_experimental_any
(macro constant)
Defined in header 
<experimental/string_view>  __cpp_lib_experimental_string_view
(macro constant)
Defined in header 
<experimental/tuple>  __cpp_lib_experimental_apply
(macro constant)
Defined in header 
<experimental/type_traits>  __cpp_lib_experimental_type_trait_variable_templates
(macro constant)
__cpp_lib_experimental_invocation_type
(macro constant)
Defined in header 
<experimental/functional>  __cpp_lib_experimental_boyer_moore_searching
(macro constant)
__cpp_lib_experimental_function_erased_allocator
(macro constant)
Defined in header 
<experimental/future>  __cpp_lib_experimental_promise_erased_allocator
(macro constant)
__cpp_lib_experimental_packaged_task_erased_allocator
(macro constant)
Defined in header 
<experimental/memory>  __cpp_lib_experimental_shared_ptr_arrays
(macro constant)
Defined in header 
<experimental/memory_resource>  __cpp_lib_experimental_memory_resources
(macro constant)
Defined in header 
<experimental/algorithm>  __cpp_lib_experimental_sample
(macro constant)
[edit] Merged into C++17
The following components of ISO/IEC TS 19568:2015 were included into C++17.
[edit] optional objects
Defined in header 
<experimental/optional>  [edit] class any
Defined in header 
<experimental/any>  [edit] string_view
Defined in header 
<experimental/string_view>  [edit] Type-erased and polymorphic allocators
[edit] Polymorphic allocators and memory resources
The entities in this section are declared in the std::experimental::pmr namespace.
Defined in header 
<experimental/memory_resource>   
 a thread-safe memory_resource  for managing allocations in pools of different block sizes 
(class) [edit]
(class) [edit]
 
 a thread-unsafe memory_resource  for managing allocations in pools of different block sizes 
(class) [edit]
(class) [edit]
 
 a special-purpose memory_resource that releases the allocated memory only when the resource is destroyed 
(class)
(class)
 
 an allocator that supports run-time polymorphism based on the memory_resource it is constructed with 
(class template)
(class template)
 
 returns a static program-wide 
(function) [edit]
memory_resource that uses the global operator new  and operator delete  to allocate and deallocate memory (function) [edit]
[edit] Convenience aliases for containers using polymorphic allocators
Convenience aliases and alias templates for containers using polymorphic allocators are provided in the std::experimental::pmr namespace for the following class templates in the standard library:
| List of container templates for which convenience aliases are provided | 
|---|
[edit]
Defined in header 
<experimental/memory>   Class
 Description
 
 
[edit] Sampling and searching algorithms
Defined in header 
<experimental/algorithm>  Defined in header 
<experimental/functional>   
 helper function to create a boyer_moore_horspool_searcher 
(function template)
(function template)
[edit] General utilities
Defined in header 
<experimental/tuple>  In addition, the TS provides numerous constexpr variable templates for the following type traits and other class templates in the standard library: