final class UnitConcentrationMass
Citizens in Foundation
A type with a customized textual representation suitable for debugging purposes.
A type with a customized textual representation.
A type that can be compared for value equality.
A type that can be hashed into a
Hasherto produce an integer hash value.
NSCodingprotocol declares the two methods that a class must implement so that instances of that class can be encoded and decoded. This capability provides the basis for archiving (where objects and other structures are stored on disk) and distribution (where objects are copied to different address spaces).
NSCopyingprotocol declares a method for providing functional copies of an object. The exact meaning of “copy” can vary from class to class, but a copy must be a functionally independent object with values identical to the original at the time the copy was made.
NSObjectProtocolgroups methods that are fundamental to all Foundation objects.
Conforming to the
NSSecureCodingprotocol indicates that an object handles encoding and decoding instances of itself in a manner that is robust against object substitution attacks.