Difference between revisions of "cpp/experimental/lib extensions"
From cppreference.com
< cpp | experimental
m (→Feature test macros: rm redundant) |
Andreas Krug (Talk | contribs) m (fmt) |
||
| (12 intermediate revisions by 8 users not shown) | |||
| Line 2: | Line 2: | ||
{{cpp/experimental/lib_extensions/navbar}} | {{cpp/experimental/lib_extensions/navbar}} | ||
| − | + | Version 1 of the C++ Extensions for Library Fundamentals, ISO/IEC TS 19568:2015 defines the following new components for the C++ standard library: | |
| + | |||
| + | ==Not selected for inclusion in C++17== | ||
| + | The following components of ISO/IEC TS 19568:2015 were not selected for inclusion in C++17. | ||
| + | |||
| + | ====Modified versions of existing classes to support type-erased allocators==== | ||
| + | {{dsc begin}} | ||
| + | {{dsc header|experimental/functional}} | ||
| + | {{dsc tclass|cpp/experimental/function|a modified version of {{lc|std::function}} with support for type-erased allocators}} | ||
| + | {{dsc header|experimental/future}} | ||
| + | {{dsc tclass|cpp/experimental/lib extensions/promise|a modified version of {{lc|std::promise}} with support for type-erased allocators}} | ||
| + | {{dsc tclass|cpp/experimental/lib extensions/packaged_task|a modified version of {{lc|std::packaged_task}} with support for type-erased allocators}} | ||
| + | {{dsc end}} | ||
| + | |||
| + | ====Memory resource adaptors==== | ||
| + | {{dsc begin}} | ||
| + | {{dsc talias|cpp/experimental/resource_adaptor|adapts an allocator into a {{lc|memory_resource}}}} | ||
| + | {{dsc end}} | ||
| + | |||
| + | ===General utilities=== | ||
| + | {{dsc begin}} | ||
| + | {{dsc header|experimental/utility}} | ||
| + | {{dsc class|cpp/experimental/erased_type|placeholder type for type erasure, such as in allocators}} | ||
| + | {{dsc header|experimental/type_traits}} | ||
| + | {{dsc tclass|cpp/experimental/invocation_type|title=invocation_type<br/>raw_invocation_type|deduce the implied function type of the callable object when called with the given argument types}} | ||
| + | {{dsc end}} | ||
| + | |||
| + | ===Feature test macros=== | ||
| + | {{dsc begin}} | ||
| + | {{dsc header|experimental/optional}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_optional|nolink=true|a value of at least {{c|201411}} indicates that the optional type is supported}} | ||
| + | {{dsc header|experimental/any}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_any|nolink=true|a value of at least {{c|201411}} indicates that the any type is supported}} | ||
| + | {{dsc header|experimental/string_view}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_string_view|nolink=true|a value of at least {{c|201411}} indicates that basic_string_view template is supported}} | ||
| + | {{dsc header|experimental/tuple}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_apply|nolink=true|a value of at least {{c|201402}} indicates that the tuple apply() function is supported}} | ||
| + | {{dsc header|experimental/type_traits}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_type_trait_variable_templates|nolink=true|a value of at least {{c|201402}} indicates that variable template type traits are supported}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_invocation_type|nolink=true|a value of at least {{c|201406}} indicates that invocation type traits are supported}} | ||
| + | {{dsc header|experimental/functional}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_boyer_moore_searching|nolink=true|a value of at least {{c|201411}} indicates that additional searching algorithms are supported}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_function_erased_allocator|nolink=true|a value of at least {{c|201406}} indicates that type-erased allocator for std::function is supported}} | ||
| + | {{dsc header|experimental/future}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_promise_erased_allocator|nolink=true|a value of at least {{c|201406}} indicates that type-erased allocator for std::promise is supported}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_packaged_task_erased_allocator|nolink=true|a value of at least {{c|201406}} indicates that type-erased allocator for std::packaged_task is supported}} | ||
| + | {{dsc header|experimental/memory}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_shared_ptr_arrays|nolink=true|a value of at least {{c|201406}} indicates that shared_ptr arrays are supported}} | ||
| + | {{dsc header|experimental/memory_resource}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_memory_resources|nolink=true|a value of at least {{c|201402}} indicates that polymorphic memory resources are supported}} | ||
| + | {{dsc header|experimental/algorithm}} | ||
| + | {{dsc macro const|__cpp_lib_experimental_sample|nolink=true|a value of {{c|201402}} indicates that the sample algorithm is supported}} | ||
| + | {{dsc end}} | ||
| + | |||
| + | ==Merged into C++17== | ||
| + | The following components of ISO/IEC TS 19568:2015 were included into C++17. | ||
===optional objects=== | ===optional objects=== | ||
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc header | experimental/optional }} | + | {{dsc header|experimental/optional}} |
| − | {{dsc tclass | cpp/experimental/optional | a class template representing ''optional objects''}} | + | {{dsc tclass|cpp/experimental/optional|a class template representing ''optional objects''}} |
{{dsc end}} | {{dsc end}} | ||
| − | === class {{tt|any}} === | + | ===class {{tt|any}}=== |
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc header | experimental/any }} | + | {{dsc header|experimental/any}} |
| − | {{dsc class | cpp/experimental/any | a type-safe container for single values of any type}} | + | {{dsc class|cpp/experimental/any|a type-safe container for single values of any type}} |
{{dsc end}} | {{dsc end}} | ||
| − | === {{tt|string_view}} === | + | ==={{tt|string_view}}=== |
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc header | experimental/string_view }} | + | {{dsc header|experimental/string_view}} |
| − | {{dsc tclass | cpp/experimental/basic_string_view | a non-owning reference to a string }} | + | {{dsc tclass|cpp/experimental/basic_string_view|a non-owning reference to a string}} |
{{dsc end}} | {{dsc end}} | ||
| − | === Type-erased and polymorphic allocators === | + | ===Type-erased and polymorphic allocators=== |
| − | ==== Polymorphic allocators and memory resources ==== | + | ====Polymorphic allocators and memory resources==== |
The entities in this section are declared in the {{lc|std::experimental::pmr}} namespace. | The entities in this section are declared in the {{lc|std::experimental::pmr}} namespace. | ||
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc header | experimental/memory_resource}} | + | {{dsc header|experimental/memory_resource}} |
| − | {{dsc class | cpp/experimental/memory_resource | | + | {{dsc class|cpp/experimental/memory_resource| an abstract interface for classes that encapsulate memory resources}} |
{{dsc inc|cpp/experimental/pmr/dsc synchronized_pool_resource}} | {{dsc inc|cpp/experimental/pmr/dsc synchronized_pool_resource}} | ||
{{dsc inc|cpp/experimental/pmr/dsc unsynchronized_pool_resource}} | {{dsc inc|cpp/experimental/pmr/dsc unsynchronized_pool_resource}} | ||
| − | {{dsc class | cpp/experimental/monotonic_buffer_resource | a special-purpose {{lc|memory_resource}} that releases the allocated memory only when the resource is destroyed}} | + | {{dsc class|cpp/experimental/monotonic_buffer_resource|a special-purpose {{lc|memory_resource}} that releases the allocated memory only when the resource is destroyed}} |
| − | {{dsc tclass | cpp/experimental/polymorphic_allocator | an allocator that supports run-time polymorphism based on the {{lc|memory_resource}} it is constructed with | + | {{dsc tclass|cpp/experimental/polymorphic_allocator|an allocator that supports run-time polymorphism based on the {{lc|memory_resource}} it is constructed with}} |
| − | + | {{dsc inc|cpp/experimental/pmr/dsc new_delete_resource}} | |
| − | {{dsc inc | cpp/experimental/pmr/dsc new_delete_resource}} | + | {{dsc inc|cpp/experimental/pmr/dsc null_memory_resource}} |
| − | {{dsc inc | cpp/experimental/pmr/dsc null_memory_resource}} | + | {{dsc inc|cpp/experimental/pmr/dsc get_default_resource}} |
| − | {{dsc inc | cpp/experimental/pmr/dsc get_default_resource}} | + | {{dsc inc|cpp/experimental/pmr/dsc set_default_resource}} |
| − | {{dsc inc | cpp/experimental/pmr/dsc set_default_resource}} | + | |
{{dsc end}} | {{dsc end}} | ||
| − | + | ====Convenience aliases for containers using polymorphic allocators==== | |
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | ==== Convenience aliases for containers using polymorphic allocators ==== | + | |
[[cpp/experimental/lib extensions/pmr_container|Convenience aliases and alias templates]] for containers using polymorphic allocators are provided in the {{tt|std::experimental::pmr}} namespace for the following class templates in the standard library: | [[cpp/experimental/lib extensions/pmr_container|Convenience aliases and alias templates]] for containers using polymorphic allocators are provided in the {{tt|std::experimental::pmr}} namespace for the following class templates in the standard library: | ||
| − | {{collapse top | List of container templates for which convenience aliases are provided}} | + | {{collapse top|List of container templates for which convenience aliases are provided}} |
{{div col|3}} | {{div col|3}} | ||
* {{lc|std::vector}} | * {{lc|std::vector}} | ||
| Line 71: | Line 116: | ||
{{collapse bottom}} | {{collapse bottom}} | ||
| − | === Array support for {{tt|shared_ptr}} === | + | ===Array support for {{tt|shared_ptr}}=== |
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc header | experimental/memory}} | + | {{dsc header|experimental/memory}} |
| − | {{dsc hitem | Class | Description}} | + | {{dsc hitem|Class|Description}} |
| − | {{dsc tclass | cpp/experimental/shared_ptr | | + | {{dsc tclass|cpp/experimental/shared_ptr|a modified version of {{lc|std::shared_ptr}} that supports arrays}} |
| − | {{dsc tclass | cpp/experimental/weak_ptr| | + | {{dsc tclass|cpp/experimental/weak_ptr|a modified version of {{lc|std::weak_ptr}} that supports arrays}} |
{{dsc end}} | {{dsc end}} | ||
===Sampling and searching algorithms=== | ===Sampling and searching algorithms=== | ||
{{dsc begin}} | {{dsc begin}} | ||
| − | {{dsc header | experimental/algorithm }} | + | {{dsc header|experimental/algorithm}} |
| − | {{dsc tfun | cpp/experimental/sample | selects n random elements from a sequence }} | + | {{dsc tfun|cpp/experimental/sample|selects n random elements from a sequence}} |
| − | {{dsc tfun | cpp/experimental/search | applies a Searcher to a sequence }} | + | {{dsc tfun|cpp/experimental/search|applies a Searcher to a sequence}} |
| − | {{dsc header | experimental/functional }} | + | {{dsc header|experimental/functional}} |
| − | {{dsc tclass | cpp/experimental/default_searcher | standard C++ library search algorithm implementation }} | + | {{dsc tclass|cpp/experimental/default_searcher|standard C++ library search algorithm implementation}} |
| − | {{dsc tfun | cpp/experimental/default_searcher | title=make_default_searcher | helper function to create a default_searcher }} | + | {{dsc tfun|cpp/experimental/default_searcher|title=make_default_searcher|helper function to create a default_searcher}} |
| − | {{dsc tclass | cpp/experimental/boyer_moore_searcher | Boyer-Moore search algorithm implementation}} | + | {{dsc tclass|cpp/experimental/boyer_moore_searcher|Boyer-Moore search algorithm implementation}} |
| − | {{dsc tfun | cpp/experimental/boyer_moore_searcher | title=make_boyer_moore_searcher | helper function to create a boyer_moore_searcher }} | + | {{dsc tfun|cpp/experimental/boyer_moore_searcher|title=make_boyer_moore_searcher|helper function to create a boyer_moore_searcher}} |
| − | {{dsc tclass | cpp/experimental/boyer_moore_horspool_searcher | Boyer-Moore-Horspool search algorithm implementation }} | + | {{dsc tclass|cpp/experimental/boyer_moore_horspool_searcher|Boyer-Moore-Horspool search algorithm implementation}} |
| − | {{dsc tfun | cpp/experimental/boyer_moore_horspool_searcher | title= make_boyer_moore_horspool_searcher | helper function to create a boyer_moore_horspool_searcher }} | + | {{dsc tfun|cpp/experimental/boyer_moore_horspool_searcher|title= make_boyer_moore_horspool_searcher|helper function to create a boyer_moore_horspool_searcher}} |
{{dsc end}} | {{dsc end}} | ||
===General utilities=== | ===General utilities=== | ||
{{dsc begin}} | {{dsc begin}} | ||
| − | + | {{dsc header|experimental/tuple}} | |
| − | + | {{dsc tfun|cpp/experimental/apply|calls a function to a tuple of arguments}} | |
| − | {{dsc header | experimental/tuple }} | + | |
| − | {{dsc tfun | cpp/experimental/apply | calls a function to a tuple of arguments | + | |
| − | + | ||
| − | + | ||
{{dsc end}} | {{dsc end}} | ||
In addition, the TS provides [[cpp/experimental/type_trait_variable_templates|numerous {{tt|constexpr}} variable templates]] for the following type traits and other class templates in the standard library: | In addition, the TS provides [[cpp/experimental/type_trait_variable_templates|numerous {{tt|constexpr}} variable templates]] for the following type traits and other class templates in the standard library: | ||
| − | {{collapse top| List of type traits and other class templates for which variable templates are provided}} | + | {{collapse top|List of type traits and other class templates for which variable templates are provided}} |
{{div col|2}} | {{div col|2}} | ||
* {{lc|std::is_void}} | * {{lc|std::is_void}} | ||
| Line 187: | Line 228: | ||
{{collapse bottom}} | {{collapse bottom}} | ||
| − | + | {{langlinks|de|es|ja|ru|zh}} | |
| − | {{ | + | |
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
| − | + | ||
Latest revision as of 00:10, 28 November 2023
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> | |
| a modified version of std::function with support for type-erased allocators (class template) | |
| Defined in header
<experimental/future> | |
| a modified version of std::promise with support for type-erased allocators (class template) | |
| a modified version of std::packaged_task with support for type-erased allocators (class template) | |
[edit] Memory resource adaptors
| adapts an allocator into a memory_resource (alias template) |
[edit] General utilities
| Defined in header
<experimental/utility> | |
| placeholder type for type erasure, such as in allocators (class) | |
| Defined in header
<experimental/type_traits> | |
| deduce the implied function type of the callable object when called with the given argument types (class template) | |
[edit] Feature test macros
| Defined in header
<experimental/optional> | |
| __cpp_lib_experimental_optional |
a value of at least 201411 indicates that the optional type is supported (macro constant) |
| Defined in header
<experimental/any> | |
| __cpp_lib_experimental_any |
a value of at least 201411 indicates that the any type is supported (macro constant) |
| Defined in header
<experimental/string_view> | |
| __cpp_lib_experimental_string_view |
a value of at least 201411 indicates that basic_string_view template is supported (macro constant) |
| Defined in header
<experimental/tuple> | |
| __cpp_lib_experimental_apply |
a value of at least 201402 indicates that the tuple apply() function is supported (macro constant) |
| Defined in header
<experimental/type_traits> | |
| __cpp_lib_experimental_type_trait_variable_templates |
a value of at least 201402 indicates that variable template type traits are supported (macro constant) |
| __cpp_lib_experimental_invocation_type |
a value of at least 201406 indicates that invocation type traits are supported (macro constant) |
| Defined in header
<experimental/functional> | |
| __cpp_lib_experimental_boyer_moore_searching |
a value of at least 201411 indicates that additional searching algorithms are supported (macro constant) |
| __cpp_lib_experimental_function_erased_allocator |
a value of at least 201406 indicates that type-erased allocator for std::function is supported (macro constant) |
| Defined in header
<experimental/future> | |
| __cpp_lib_experimental_promise_erased_allocator |
a value of at least 201406 indicates that type-erased allocator for std::promise is supported (macro constant) |
| __cpp_lib_experimental_packaged_task_erased_allocator |
a value of at least 201406 indicates that type-erased allocator for std::packaged_task is supported (macro constant) |
| Defined in header
<experimental/memory> | |
| __cpp_lib_experimental_shared_ptr_arrays |
a value of at least 201406 indicates that shared_ptr arrays are supported (macro constant) |
| Defined in header
<experimental/memory_resource> | |
| __cpp_lib_experimental_memory_resources |
a value of at least 201402 indicates that polymorphic memory resources are supported (macro constant) |
| Defined in header
<experimental/algorithm> | |
| __cpp_lib_experimental_sample |
a value of 201402 indicates that the sample algorithm is supported (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> | |
| a class template representing optional objects (class template) | |
[edit] class any
| Defined in header
<experimental/any> | |
| a type-safe container for single values of any type (class) | |
[edit] string_view
| Defined in header
<experimental/string_view> | |
| a non-owning reference to a string (class template) | |
[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> | |
| an abstract interface for classes that encapsulate memory resources (class) | |
| a thread-safe memory_resource for managing allocations in pools of different block sizes (class) | |
| a thread-unsafe memory_resource for managing allocations in pools of different block sizes (class) | |
| a special-purpose memory_resource that releases the allocated memory only when the resource is destroyed (class) | |
| an allocator that supports run-time polymorphism based on the memory_resource it is constructed with (class template) | |
returns a static program-wide memory_resource that uses the global operator new and operator delete to allocate and deallocate memory (function) | |
returns a static memory_resource that performs no allocation (function) | |
gets the default memory_resource (function) | |
sets the default memory_resource (function) | |
[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 |
| a modified version of std::shared_ptr that supports arrays (class template) | |
| a modified version of std::weak_ptr that supports arrays (class template) | |
[edit] Sampling and searching algorithms
| Defined in header
<experimental/algorithm> | |
| selects n random elements from a sequence (function template) | |
| applies a Searcher to a sequence (function template) | |
| Defined in header
<experimental/functional> | |
| standard C++ library search algorithm implementation (class template) | |
| helper function to create a default_searcher (function template) | |
| Boyer-Moore search algorithm implementation (class template) | |
| helper function to create a boyer_moore_searcher (function template) | |
| Boyer-Moore-Horspool search algorithm implementation (class template) | |
| helper function to create a boyer_moore_horspool_searcher (function template) | |
[edit] General utilities
| Defined in header
<experimental/tuple> | |
| calls a function to a tuple of arguments (function template) | |
In addition, the TS provides numerous constexpr variable templates for the following type traits and other class templates in the standard library:
