Target object on which to define the read-only properties
Object specifying the mapping of the read-only properties to the source properties; the keys of the object are the read-only property names and the values are either a function that returns the value of the property or a string which is the name of the source property
Optionaloptions: { configurable?: boolean; enumerable?: boolean }The target object with the defined read-only properties
Define read-only properties on the target object which are mapped to the source properties specified in the
propertiesparameter. The read-only properties are defined as non-enumerable and configurable.