IGListKit/Source/Common/IGListDiffable.h
Ryan Nystrom 000bc36919 Relicense to MIT
Summary: Relicensing IGListKit under MIT

Reviewed By: calimarkus

Differential Revision: D7764125

fbshipit-source-id: 6c773195ef3184202725fe7f08de754f979cb83f
2018-05-01 14:50:56 -07:00

38 lines
1.1 KiB
Objective-C

/**
* Copyright (c) 2016-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
#import <Foundation/Foundation.h>
/**
The `IGListDiffable` protocol provides methods needed to compare the identity and equality of two objects.
*/
NS_SWIFT_NAME(ListDiffable)
@protocol IGListDiffable
/**
Returns a key that uniquely identifies the object.
@return A key that can be used to uniquely identify the object.
@note Two objects may share the same identifier, but are not equal. A common pattern is to use the `NSObject`
category for automatic conformance. However this means that objects will be identified on their
pointer value so finding updates becomes impossible.
@warning This value should never be mutated.
*/
- (nonnull id<NSObject>)diffIdentifier;
/**
Returns whether the receiver and a given object are equal.
@param object The object to be compared to the receiver.
@return `YES` if the receiver and object are equal, otherwise `NO`.
*/
- (BOOL)isEqualToDiffableObject:(nullable id<IGListDiffable>)object;
@end