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Adopted By:
Various OpenStep classes

Declared In:

Protocol Description

The NSMutableCopying protocol declares a method for providing mutable copies of an object. Only classes that define an "immutable vs. mutable" distinction should adopt this protocol. Classes that don't define such a distinction should adopt NSCopying instead.

NSMutableCopying declares one method, mutableCopyWithZone:, but mutable copying is commonly invoked with the convenience method mutableCopy. The mutableCopy method is defined for all NSObjects and simply invokes mutableCopyWithZone: with the default zone.

See the NSCopying protocol for details on implementing copying behavior.

Instance Methods


- mutableCopyWithZone:(NSZone *)zone

Returns a new instance that's a mutable copy of the receiver. Memory for the new instance is allocated from zone, which may be NULL. If zone is NULL, the new instance is allocated from the default zone, which is returned by NSDefaultMallocZone(). The returned object is implicitly retained by the sender, who is responsible for releasing it. The copy returned is mutable whether the original is mutable or not.

See also: - copyWithZone: (NSCopying protocol), - mutableCopy (NSObject)

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