fling_units 0.4.0

Dependency-free, type-safe Dart unit conversion library. Decouple specific unit types you need to work with from the rest of your code.

A type safe Dart library for unit conversion.

Usage

Create an instance of the dimension type you want to measure:

FlingUnits.Distance distanceToSeattle = FlingUnits.Distance.kilometers(246);
FlingUnits.Distance distanceToTheMoon = FlingUnits.Distance(miles: 238900, feet: 42, inches: 6.3);

Convert to any other type within that dimension:

double distanceToSeattleInMiles = distanceToSeattle.miles;
double distanceToSeattleInInches = distanceToSeattle.inches;

Perform basic arithmetic:

FlingUnits.Distance distanceToSeattleAndBack = distanceToSeattle * 2;
FlingUnits.Distance distanceToTheMoon = distanceToUpperAtmosphere + distanceFromAtmosphereToMoon;
FlingUnits.Distance distanceToTheEndsOfTheUniverse = FlingUnits.Distance.infinity();
bool useTheCar = distanceToTravel >= FlingUnits.Distance.miles(1.5);

Built-in ordering:

[Distance.zero(), Distance.infinity(), Distance.meters(3), Distance.feet(3), Distance.meters(-2)].sort();
// produces [Distance.meters(-2), Distance.zero(), Distance.feet(3), Distance.meters(3), Distance.infinity()]

Abstract away the specific units your code needs by passing around the encapsulated types. It doesn't matter which units each portion of your code requires, they can be combined seamlessly:

FlingUnits.Distance computeTotalDistanceWithWiggleRoom(final FlingUnits.Distance targetDistance) {
  return targetDistance + FlingUnits.Distance.meters(3.0);
}

Ensure type safety:

var nonsense = distanceToSeattle + temperatureInNewYork;  // won't compile!

Supported Features

Distance

Units

Metric

• millimeters
• centimeters
• decimeters
• meters
• dekameters
• hectometers
• kilometers

Imperial

• inches
• feet
• yards
• miles

Nautical

• nautical miles

Operations

• implements Comparable<Distance> for built-in ordering
• compare two Distances (>, <, ==, !=, >=, <=)
• add or subtract two Distances (+, -)
• multiply or divide a Distance by a scalar (*, /)
• negate a Distance (unary -)

Volume

Units

Metric

• milliliters
• centiliters
• deciliters
• liters
• dekaliters
• hectoliters
• kiloliters
• cubic meter

Imperial

• teaspoon
• tablespoon
• fluid ounce
• cup
• pint
• quart
• gallon
• cubic foot
• cubic inch

US

• teaspoon
• tablespoon
• fluid ounce
• cup
• pint
• quart
• gallon

Operations

• implements Comparable<Volume> for built-in ordering
• compare two Volumes (>, <, ==, !=, >=, <=)
• add or subtract two Volumes (+, -)
• multiply or divide a Volume by a scalar (*, /)
• negate a Volume (unary -)

Temperature

Units

• kelvin
• celcius
• fahrenheit

Operations

• Temperature implements Comparable<Temperature> for built-in ordering
• TemperatureChange implements Comparable<TemperatureChange> for built-in ordering
• compare two Temperatures (>, <, ==, !=, >=, <=)
• compare two TemperatureChanges (>, <, ==, !=, >=, <=)
• add or subtract TemperatureChanges to or from Temperatures (+, -)
• add or subtract TemperatureChanges to or from other TemperatureChanges (+, -)
• multiply or divide TemperatureChanges by a scalar (*, /)
• negate a TemperatureChange (unary -)