std::floating_point (since C++20)

 

C++

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Concepts library

Core language concepts same_as (C++20) derived_from (C++20) convertible_to (C++20) common_reference_with (C++20) common_with (C++20) integral (C++20) signed_integral (C++20) unsigned_integral (C++20) floating_point (C++20) swappableswappable_with (C++20)(C++20) destructible (C++20) constructible_from (C++20) default_initializable (C++20)   move_constructible (C++20) copy_constructible (C++20) assignable_from (C++20)

Comparison concepts equality_comparableequality_comparable_with (C++20)(C++20) totally_orderedtotally_ordered_with (C++20)(C++20) Object concepts movable (C++20) copyable (C++20) semiregular (C++20) regular (C++20) Callable concepts invocableregular_invocable (C++20)(C++20) predicate (C++20) relation (C++20) equivalence_relation (C++20) strict_weak_order (C++20)

Exposition-only concepts boolean-testable  (C++20)

 

Defined in header <concepts>
template< class T > concept floating_point = std::is_floating_point_v<T>;		(since C++20)

The concept floating_point<T> is satisfied if and only if T is a floating-point type.

Example

Run this code

#include <concepts>
#include <iostream>
#include <type_traits>
 
constexpr std::floating_point auto x2(std::floating_point auto x)
{
    return x + x;
}
 
constexpr std::integral auto x2(std::integral auto x)
{
    return x << 1;
}
 
int main()
{
    constexpr auto d = x2(1.1);
    static_assert(std::is_same_v<double const, decltype(d)>);
    std::cout << d << '\n';
 
    constexpr auto f = x2(2.2f);
    static_assert(std::is_same_v<float const, decltype(f)>);
    std::cout << f << '\n';
 
    constexpr auto i = x2(444);
    static_assert(std::is_same_v<int const, decltype(i)>);
    std::cout << i << '\n';
}

Output:

2.2
4.4
888

References

• C++23 standard (ISO/IEC 14882:2024):

• 18.4.7 Arithmetic concepts [concepts.arithmetic]

• C++20 standard (ISO/IEC 14882:2020):

• 18.4.7 Arithmetic concepts [concepts.arithmetic]

See also

is_floating_point (C++11)

checks if a type is a floating-point type (class template)