std::numeric_limits<T>:: is_exact
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numeric_limits::is_exact
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(C++11)
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| Static member functions | ||||
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(C++11)
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| Helper types | ||||
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static
const
bool
is_exact
;
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(until C++11) | |
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static
constexpr
bool
is_exact
;
|
(since C++11) | |
The value of
std::
numeric_limits
<
T
>
::
is_exact
is
true
for all arithmetic types
T
that use exact representation.
Standard specializations
T
|
value of std:: numeric_limits < T > :: is_exact |
| /* non-specialized */ | false |
| bool | true |
| char | true |
| signed char | true |
| unsigned char | true |
| wchar_t | true |
| char8_t (since C++20) | true |
| char16_t (since C++11) | true |
| char32_t (since C++11) | true |
| short | true |
| unsigned short | true |
| int | true |
| unsigned int | true |
| long | true |
| unsigned long | true |
| long long (since C++11) | true |
| unsigned long long (since C++11) | true |
| float | false |
| double | false |
| long double | false |
Notes
While all fundamental types
T
for which
std::
numeric_limits
<
T
>
::
is_exact
==
true
are integer types, a library may define exact types that are not integers, e.g. a rational arithmetic type representing fractions.
See also
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[static]
|
identifies integer types
(public static member constant) |
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[static]
|
identifies signed types
(public static member constant) |
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[static]
|
identifies types that represent a finite set of values
(public static member constant) |