arene::base::numbers Namespace Reference

Variable Documentation

one_v

template<typename T>

T arene::base::numbers::one_v {1}

externconstexpr

The multiplicative identity of T.

Template Parameters

T	numeric type

a * one_v<T> == a and one_v<T> * a == a are true for valid values of a of type T.

Users may specialize one_v for cv-unqualified program-defined types. A specialization is required if any of the following cases are true for the expression T{1}:

• is not well formed
• does not match the required semantics
• is not invocable within a constant expression

See also

zero_v

pi_v

template<typename Type>

Type arene::base::numbers::pi_v {pi_detail::pi_v<Type>}

externconstexpr

The value of Pi, in the specified floating point type. Type must be float or double , or a type for which an explicit specialization of pi_v has been made.

Template Parameters

Type	The chosen type

zero_v

template<typename T>

T arene::base::numbers::zero_v {}

externconstexpr

The additive identity of T.

Template Parameters

T	numeric type

a + zero_v<T> == a and zero_v<T> + a == a are true for valid values of a of type T.

Users may specialize zero_v for cv-unqualified program-defined types. A specialization is required if any of the following cases are true for the expression T{}:

• is not well formed
• does not match the required semantics
• is not invocable within a constant expression

A specialization may be non-constexpr; such specializations may not be used in contexts that require a constant expression.

Example of a non-constexpr specialization (for a type whose default constructor is not constexpr but does have the correct semantics):

template <>
my_type const arene::base::numbers::zero_v<my_type>{};