example.units

package example;

// base units are declared as simple identifiers, and derived units can be expressed in terms of the base units
unit (
  M;
  S;
  MpS = M / S;
  H = S * 3600;
  KM = 1000 * M;
  KMpH = KM / H;
  NM = 1852 * M;
  KN = NM / H;
  BF;
  Min = 60*S;
)

// quantities are defined with a specified unit and a base type
quantity (
  Scalar() float64;
  Length(M) float64;
  Area(M^2) float64;
  Time(S) float64;
  Frequency(1 / S) float64;
  RPM(1 / Min) float64;
  Distance(KM) float64;
  Duration(H) float64;
  Speed(KM/H) float64;
  Beaufort(BF) int;
)

// operations are explicitly defined for each quantity
operation (
  Length * Length -> Area;
  Length % Length -> Length;
  Beaufort % Beaufort -> Beaufort;
  Length / Length -> Scalar;
  Length + Length -> Length;
  Length - Length -> Length;
  Length * Scalar -> Length;
  Time * Scalar -> Time;
  Distance / Duration -> Speed;
  Speed * Duration -> Distance;
  Scalar / Time -> Frequency;
)

conversion (
  Frequency -> RPM;
  RPM -> Frequency;
)