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NIKOLA RUSEV
5,293 Pointsconforming protocol computed properties
In protocol person we have computed stored properties that must be declared as a variable but when struct user conform to protocol person stored properties are declared as constant. Why compailer dont rise an error??? is that becouse computed stored properties are declared as gettable?
1 Answer
Jesse Gay
Full Stack JavaScript Techdegree Student 14,045 PointsI think you're on the right track. If you try to use let in the protocol definition, Xcode says "Immutable property requirement must be declared as 'var' with a '{get}' specifier." From Apple Docs: If a protocol requires a property to be gettable and settable, that property requirement cannot be fulfilled by a constant stored property or a read-only computed property. If the protocol only requires a property to be gettable, the requirement can be satisfied by any kind of property, and it is valid for the property to be also settable if this is useful for your own code.
Property requirements are always declared as variable properties, prefixed with the var keyword. Gettable and settable properties are indicated by writing { get set } after their type declaration, and gettable properties are indicated by writing { get }.