DSSparseArray and DSMutableSparseArray
These classes provide sparse array functionality for objective-c. They manage ordered collections of objects that are similar to regular arrays but can hold nil entries. The efficiency comes from the fact that a nil entry takes no space, it simply does not exist. They should be able to be used anyplace an NSArray or NSMutableArray is used but, unless the arrays actually have empty entries, are less efficient.
DSSparseArray provides immutible array functionality that can contain empty or nil entries.
DSMutableSparseArray provides mutable array functionality that can contain empty or nil entries.
Installation and Usage
Copy the DSSparseArray.h, DSSparseArray.m, DSSparseArrayEnumerator.h, and DSSparseArrayEnumerator.m files into your project then just use like an NSArray or NSMutableArray, substituting DSSparseArray or DSMutableSparseArray. Should be compatible with iOS or Mac OS X.
The MIT License (MIT)
Copyright (c) 2014 Syntonicity, LLC
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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