mp_units::quantity_bounds

Customization point for providing bounds on a quantity point relative to an origin.

Synopsis

template<PointOrigin auto PO>
requires (PO._quantity_spec_.character == quantity_character::real_scalar)
inline constexpr auto quantity_bounds = detail::undefined;

Description

Users specialize this variable template for point origins (both absolute and relative). The value should be an overflow-policy object that stores the bounds (e.g. reflect_in_range, clamp_to_range, wrap_to_range).

Bounds are always enforced as constraints on quantity_from(Origin) — the displacement measured in the frame of the specialized origin. Different origins (including relative ones) may have independent bounds; it is the user's responsibility to keep them consistent when multiple levels of bounds are in use.

Example:

{.cpp}
 // Absolute origin: latitude reflects at poles
 inline constexpr struct equator final : absolute_point_origin<geo_latitude> {} equator;
 template<>
 constexpr auto quantity_bounds<equator> = reflect_in_range{-90 * deg, 90 * deg};

 // Relative origin: AC controller setpoint — comfort range clamped around 21 °C
 inline constexpr struct room_reference_temp final :
     relative_point_origin<point<deg_C>(21)> {} room_reference_temp;
 template<>
 constexpr auto quantity_bounds<room_reference_temp> = clamp_to_range{delta<deg_C>(-3), delta<deg_C>(3)};

Template Parameters