NSUnit is an abstract class that declares a programmatic interface for objects that represent a unit of measure.


Each instance of an NSUnit subclass consists of a symbol, which can be used to create string representations of NSMeasurement objects with the Measurement​Formatter class.

The Dimension subclass is an abstract class that represents a dimensional unit, which can be converted into different units of the same type. The Foundation framework provides several concrete Dimension subclasses to represent the most common physical quantities, including mass, length, duration, and speed.

Subclassing Notes

NSUnit is intended for subclassing. For dimensional units, you should use one of the Apple provided Dimension subclasses listed in , or create a custom subclass of Dimension. You can create a direct subclass of NSUnit to represent a custom dimensionless unit, such as a count, score, or ratio.


Accessing Properties

var symbol:​ String

The symbolic representation of the unit.

Creating Units

init(symbol:​ String)

Initializes a new unit with the specified symbol.