MDCDamerauLevenshtein 0.1.0

You want to add pod 'MDCDamerauLevenshtein', '~> 0.1' similar to the following to your Podfile:

target 'MyApp' do
  pod 'MDCDamerauLevenshtein', '~> 0.1'
end

Then run a pod install inside your terminal, or from CocoaPods.app.

Alternatively to give it a test run, run the command:

pod try MDCDamerauLevenshtein

Categories to calculate the edit distance between NSString objects.

MDCDamerauLevenshtein includes two algorithms for calculating the edit distance between NSString objects:

Levenshtein distance calculates the number of insertions, deletions, and substitions necessary in order to convert one string into the other.
Damerau-Levenshtein improves upon Levenshtein to include the transposition of two adjacent characters. Damerau states that some combination of the four operations make up for 80% of all human spelling errors.

Potential applications for this library:

Don't just use -[NSString compare:options:] to filter search results, display terms with small edit distances.
...and many more!

Other Implementations

koyachi/NSString-LevenshteinDistance also provides categories on NSString, but only computes Levenshtein distance, not Damerau-Levenshtein. Does not include unit tests.