Difference between revisions of "cpp/types"

Latest revision as of 07:49, 9 April 2024

Defined in header `<cstddef>`
size_t	unsigned integer type returned by the `sizeof` operator (typedef) [edit]
ptrdiff_t	signed integer type returned when subtracting two pointers (typedef) [edit]
nullptr_t (C++11)	the type of the null pointer literal `nullptr` (typedef) [edit]
NULL	implementation-defined null pointer constant (macro constant) [edit]
max_align_t (C++11)	trivial type with alignment requirement as great as any other scalar type (typedef) [edit]
offsetof	byte offset from the beginning of a standard-layout type to specified member (function macro) [edit]
byte (C++17)	the byte type (enum) [edit]


Defined in header `<cstdbool>`(deprecated) (until C++20)
Defined in header `<stdbool.h>`
__bool_true_false_are_defined (C++11)(deprecated)	C compatibility macro constant, expands to integer literal 1 (macro constant) [edit]

Defined in header `<cstdalign>`(deprecated) (until C++20)
Defined in header `<stdalign.h>`
__alignas_is_defined (C++11)(deprecated)	C compatibility macro constant, expands to integer literal 1 (macro constant) [edit]
__alignof_is_defined (C++11)(deprecated)	C compatibility macro constant, expands to integer literal 1 (macro constant) [edit]

[edit] Fixed width integer types (since C++11)

[edit] Fixed width floating-point types (since C++23)

[edit] Numeric limits

Defined in header `<limits>`
numeric_limits	provides an interface to query properties of all fundamental numeric types (class template) [edit]

[edit] C numeric limits interface

[edit] Runtime type identification

Defined in header `<typeinfo>`
type_info	contains some type’s information, the class returned by the typeid operator (class) [edit]
bad_typeid	exception that is thrown if an argument in a typeid expression is null (class) [edit]
bad_cast	exception that is thrown by an invalid `dynamic_cast` expression, i.e. a cast of reference type fails (class) [edit]

Defined in header `<typeindex>`
type_index (C++11)	wrapper around a `type_info` object, that can be used as index in associative and unordered associative containers (class) [edit]

[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 4036	C++11	`__alignof_is_defined` was underspecified in the C++ standard	specified and deprecated

[edit] See also

Type traits and metaprogramming library
C documentation for Type support library

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Language
Standard library
Standard library headers
Named requirements
Feature test macros (C++20)
Language support library
Concepts library (C++20)
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General utilities library
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Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Numerics library
Localizations library
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Difference between revisions of "cpp/types"

Latest revision as of 07:49, 9 April 2024

Contents

[edit] Additional basic types and macros

[edit] Fixed width integer types (since C++11)

[edit] Fixed width floating-point types (since C++23)

[edit] Numeric limits

[edit] C numeric limits interface

[edit] Runtime type identification

[edit] Defect reports

[edit] See also

Navigation

Toolbox

@@ Line 1: / Line 1: @@
-{{title|Type support (basic types, RTTI, type traits)}}
+{{title|Type support (basic types, RTTI)}}
 {{cpp/types/navbar}}
-<small>(See also {{ltt|cpp/language/type}} for type system overview)</small>
+See also [[cpp/language/type|type system overview]] and [[cpp/language/types|fundamental types defined by the language]].
-==Basic types==
-===[[cpp/language/types | Fundamental types defined by the language]]===
 ===Additional basic types and macros===
 {{dsc begin}}
-{{dsc header | cstddef}}
+{{dsc header|cstddef}}
-{{dsc header | stddef.h}}
+{{dsc inc|cpp/types/dsc size_t}}
-{{dsc inc | cpp/types/dsc size_t}}
+{{dsc inc|cpp/types/dsc ptrdiff_t}}
-{{dsc inc | cpp/types/dsc ptrdiff_t}}
+{{dsc inc|cpp/types/dsc nullptr_t}}
-{{dsc inc | cpp/types/dsc nullptr_t}}
+{{dsc inc|cpp/types/dsc NULL}}
-{{dsc inc | cpp/types/dsc NULL}}
+{{dsc inc|cpp/types/dsc max_align_t}}
-{{dsc inc | cpp/types/dsc max_align_t}}
+{{dsc inc|cpp/types/dsc offsetof}}
-{{dsc inc | cpp/types/dsc offsetof}}
+{{dsc inc|cpp/types/dsc byte}}
-{{dsc header | cstddef}}
-{{dsc inc | cpp/types/dsc byte}}
 {{dsc break}}
 {{dsc sep}}
-{{dsc header | cstdbool | {{mark deprecated}} {{mark until c++20}} }}
+{{dsc header|cstdbool|{{mark deprecated}} {{mark until c++20}}}}
-{{dsc header | stdbool.h}}
+{{dsc header|stdbool.h}}
-{{dsc inc | cpp/types/dsc bool_true_false_are_defined}}
+{{dsc inc|cpp/types/dsc bool_true_false_are_defined}}
 {{dsc sep}}
-{{dsc header | cstdalign| {{mark deprecated}} {{mark until c++20}} }}
+{{dsc header|cstdalign|{{mark deprecated}} {{mark until c++20}}}}
-{{dsc header | stdalign.h}}
+{{dsc header|stdalign.h}}
-{{dsc inc | cpp/types/dsc alignas_is_defined}}
+{{dsc inc|cpp/types/dsc alignas_is_defined}}
+{{dsc inc|cpp/types/dsc alignof_is_defined}}
 {{dsc end}}
-===[[cpp/types/integer | Fixed width integer types]] {{mark since c++11}}===
+===[[cpp/types/integer|Fixed width integer types]] {{mark since c++11}}===
-==Numeric limits==
+===[[cpp/types/floating-point|Fixed width floating-point types]] {{mark since c++23}}===
+===Numeric limits===
 {{dsc begin}}
-{{dsc header | limits}}
+{{dsc header|limits}}
-{{dsc inc | cpp/types/dsc numeric_limits}}
+{{dsc inc|cpp/types/dsc numeric_limits}}
 {{dsc end}}
-===[[cpp/types/climits|C numeric limits interface]]===
+====[[cpp/types/climits|C numeric limits interface]]====
-==Runtime type identification==
+===Runtime type identification===
 {{dsc begin}}
-{{dsc header | typeinfo}}
+{{dsc header|typeinfo}}
-{{dsc inc | cpp/types/dsc type_info}}
+{{dsc inc|cpp/types/dsc type_info}}
-{{dsc inc | cpp/types/dsc bad_typeid}}
+{{dsc inc|cpp/types/dsc bad_typeid}}
-{{dsc inc | cpp/types/dsc bad_cast}}
+{{dsc inc|cpp/types/dsc bad_cast}}
 {{dsc sep}}
-{{dsc header | typeindex}}
+{{dsc header|typeindex}}
-{{dsc inc | cpp/types/dsc type_index}}
+{{dsc inc|cpp/types/dsc type_index}}
 {{dsc end}}
-==<span id="Type_traits">Type traits {{mark since c++11}}</span>==
+===Defect reports===
+{{dr list begin}}
-Type traits defines a compile-time template-based interface to query or modify the properties of types.
+{{dr list item|wg=lwg|dr=4036|std=C++11|before={{tt|__alignof_is_defined}} was underspecified in the C++ standard|after=specified and deprecated}}
+{{dr list end}}
-Attempting to specialize a template defined in the {{tt|<type_traits>}} header results in undefined behavior, except that {{lc|std::common_type}} may be specialized [[cpp/types/common_type#Specializations|as described in its description]].
-A template defined in the {{tt|<type_traits>}} header may be instantiated with an incomplete type unless otherwise specified, notwithstanding the general prohibition against instantiating standard library templates with incomplete types.
-===Type properties===
-{{dsc begin}}
-{{dsc header | type_traits}}
-{{dsc h2 | Primary type categories}}
-{{dsc inc | cpp/types/dsc is_void}}
-{{dsc inc | cpp/types/dsc is_null_pointer}}
-{{dsc inc | cpp/types/dsc is_integral}}
-{{dsc inc | cpp/types/dsc is_floating_point}}
-{{dsc inc | cpp/types/dsc is_array}}
-{{dsc inc | cpp/types/dsc is_enum}}
-{{dsc inc | cpp/types/dsc is_union}}
-{{dsc inc | cpp/types/dsc is_class}}
-{{dsc inc | cpp/types/dsc is_function}}
-{{dsc inc | cpp/types/dsc is_pointer}}
-{{dsc inc | cpp/types/dsc is_lvalue_reference}}
-{{dsc inc | cpp/types/dsc is_rvalue_reference}}
-{{dsc inc | cpp/types/dsc is_member_object_pointer}}
-{{dsc inc | cpp/types/dsc is_member_function_pointer}}
-{{dsc h2 | Composite type categories}}
-{{dsc inc | cpp/types/dsc is_fundamental}}
-{{dsc inc | cpp/types/dsc is_arithmetic}}
-{{dsc inc | cpp/types/dsc is_scalar}}
-{{dsc inc | cpp/types/dsc is_object}}
-{{dsc inc | cpp/types/dsc is_compound}}
-{{dsc inc | cpp/types/dsc is_reference}}
-{{dsc inc | cpp/types/dsc is_member_pointer}}
-{{dsc h2 | Type properties}}
-{{dsc inc | cpp/types/dsc is_const}}
-{{dsc inc | cpp/types/dsc is_volatile}}
-{{dsc inc | cpp/types/dsc is_trivial}}
-{{dsc inc | cpp/types/dsc is_trivially_copyable}}
-{{dsc inc | cpp/types/dsc is_standard_layout}}
-{{dsc inc | cpp/types/dsc is_pod}}
-{{dsc inc | cpp/types/dsc is_literal_type}}
-{{dsc inc | cpp/types/dsc has_unique_object_representations}}
-{{dsc inc | cpp/types/dsc is_empty}}
-{{dsc inc | cpp/types/dsc is_polymorphic}}
-{{dsc inc | cpp/types/dsc is_abstract}}
-{{dsc inc | cpp/types/dsc is_final}}
-{{dsc inc | cpp/types/dsc is_aggregate}}
-{{dsc inc | cpp/types/dsc is_signed}}
-{{dsc inc | cpp/types/dsc is_unsigned}}
-{{dsc inc | cpp/types/dsc is_bounded_array}}
-{{dsc inc | cpp/types/dsc is_unbounded_array}}
-{{dsc inc | cpp/types/dsc is_scoped_enum}}
-{{dsc end}}
-{{dsc begin}}
-{{dsc h2 | Supported operations}}
-{{dsc inc | cpp/types/dsc is_constructible}}
-{{dsc inc | cpp/types/dsc is_default_constructible}}
-{{dsc inc | cpp/types/dsc is_copy_constructible}}
-{{dsc inc | cpp/types/dsc is_move_constructible}}
-{{dsc inc | cpp/types/dsc is_assignable}}
-{{dsc inc | cpp/types/dsc is_copy_assignable}}
-{{dsc inc | cpp/types/dsc is_move_assignable}}
-{{dsc inc | cpp/types/dsc is_destructible}}
-{{dsc inc | cpp/types/dsc has_virtual_destructor}}
-{{dsc inc | cpp/types/dsc is_swappable}}
-{{dsc end}}
-{{dsc begin}}
-{{dsc h2 | Property queries}}
-{{dsc inc | cpp/types/dsc alignment_of}}
-{{dsc inc | cpp/types/dsc rank}}
-{{dsc inc | cpp/types/dsc extent}}
-{{dsc end}}
-{{dsc begin}}
-{{dsc h2 | Type relationships}}
-{{dsc inc | cpp/types/dsc is_same}}
-{{dsc inc | cpp/types/dsc is_base_of}}
-{{dsc inc | cpp/types/dsc is_convertible}}
-{{dsc inc | cpp/types/dsc is_invocable}}
-{{dsc inc | cpp/types/dsc is_layout_compatible}}
-{{dsc inc | cpp/types/dsc is_pointer_interconvertible_base_of}}
-{{dsc inc | cpp/types/dsc is_pointer_interconvertible_with_class}}
-{{dsc inc | cpp/types/dsc is_corresponding_member}}
-{{dsc end}}
-{{dsc begin}}
-{{dsc h2 | Other}}
-{{dsc inc | cpp/types/dsc is_constant_evaluated}}
-{{dsc end}}
-===Type modifications===
-Type modification templates create new type definitions by applying modifications on a template parameter. The resulting type can then be accessed through {{tt|type}} member typedef.
-{{dsc begin}}
-{{dsc header | type_traits}}
-{{dsc h2 | Const-volatility specifiers}}
-{{dsc inc | cpp/types/dsc remove_cv}}
-{{dsc inc | cpp/types/dsc add_cv}}
-{{dsc h2 | References}}
-{{dsc inc | cpp/types/dsc remove_reference}}
-{{dsc inc | cpp/types/dsc add_reference}}
-{{dsc h2 | Pointers}}
-{{dsc inc | cpp/types/dsc remove_pointer}}
-{{dsc inc | cpp/types/dsc add_pointer}}
-{{dsc h2 | Sign modifiers}}
-{{dsc inc | cpp/types/dsc make_signed}}
-{{dsc inc | cpp/types/dsc make_unsigned}}
-{{dsc h2 | Arrays}}
-{{dsc inc | cpp/types/dsc remove_extent}}
-{{dsc inc | cpp/types/dsc remove_all_extents}}
-{{dsc end}}
-===Miscellaneous transformations===
-{{dsc begin}}
-{{dsc header | type_traits}}
-{{dsc inc | cpp/types/dsc aligned_storage}}
-{{dsc inc | cpp/types/dsc aligned_union}}
-{{dsc inc | cpp/types/dsc decay}}
-{{dsc inc | cpp/types/dsc remove_cvref}}
-{{dsc inc | cpp/types/dsc enable_if}}
-{{dsc inc | cpp/types/dsc conditional}}
-{{dsc inc | cpp/types/dsc common_type}}
-{{dsc inc | cpp/types/dsc common_reference}}
-{{dsc inc | cpp/types/dsc underlying_type}}
-{{dsc inc | cpp/types/dsc result_of}}
-{{dsc inc | cpp/types/dsc void_t}}
-{{dsc inc | cpp/types/dsc type_identity}}
-{{dsc end}}
-===Operations on traits===
-{{dsc begin}}
-{{dsc header | type_traits}}
-{{dsc inc | cpp/types/dsc conjunction}}
-{{dsc inc | cpp/types/dsc disjunction}}
-{{dsc inc | cpp/types/dsc negation}}
-{{dsc end}}
-===Helper classes===
-{{dsc begin}}
-{{dsc header | type_traits}}
-{{dsc inc | cpp/types/dsc integral_constant}}
-{{dsc end}}
-Two specializations of {{lc|std::integral_constant}} for the type {{c|bool}} are provided:
-{{dsc begin}}
-{{dsc header | type_traits}}
-{{dsc h2 | Specializations}}
-{{dsc hitem | Type | Definition}}
-{{dsc | {{tt|true_type}} | {{c|std::integral_constant<bool, true>}}}}
-{{dsc | {{tt|false_type}} | {{c|std::integral_constant<bool, false>}}}}
-{{dsc end}}
-==See also==
+===See also===
 {{dsc begin}}
-{{dsc see c | c/types | Type support library | nomono=true}}
+{{dsc|[[cpp/meta#Type traits|Type traits and metaprogramming library]]}}
+{{dsc see c|c/types|Type support library|nomono=true}}
 {{dsc end}}
 {{langlinks|de|es|fr|it|ja|pt|ru|zh}}