Explicit cast of a quantity point type
Declared in <mp-units/framework/quantity_cast.h>
template<
QuantitySpec auto ToQS,
typename FwdQP,
QuantityPoint QP = std::remove_cvref_t<FwdQP>>
requires (mp_units::castable(QP::quantity_spec, ToQS)) &&
requires { typename quantity_point<make_reference(ToQS, QP::unit), QP::point_origin, typename QP::rep>; }
[[nodiscard]]
constexpr
QuantityPoint auto
quantity_cast(FwdQP&& qp);This cast converts only a quantity point type. It might be used to force some quantity point type conversions that are not implicitly allowed but are allowed explicitly.
For example:
auto length = isq::length(quantity_point{42 * m});
auto altitude = quantity_cast<isq::altitude>(length);
This cast does not affect the underlying value of a number stored in a quantity point.
the quantity point with its quantity type recast to ToQS
The return value should not be discarded.
| Name | Description |
|---|---|
| ToQS | a quantity specification to use for a target quantity point |
| Name | Description |
|---|---|
| qp | the quantity point to cast |