IGListKit/Source/IGListDiffable.h
Jesse Squires 204f7d5390 Docs updates and refinements, #181
Summary:
Did a full pass on documentation.

- Clean up
- Fixes
- Better markdown

> **NOTE:** this PR does not re-gen docs. I will do that next. Before we cut 2.0
Closes https://github.com/Instagram/IGListKit/pull/198

Reviewed By: rnystrom

Differential Revision: D4181253

Pulled By: jessesquires

fbshipit-source-id: 133c4af392bb396ecc6eff0c895c55e6d18730b7
2016-11-15 11:44:10 -08:00

39 lines
1.2 KiB
Objective-C

/**
* Copyright (c) 2016-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
#import <Foundation/Foundation.h>
/**
The `IGListDiffable` protocol provides methods needed to compare the identity and equality of two objects.
*/
@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