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book/node_modules/array-difference/README.md

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+# Difference
+
+Utility method to compute the difference between two arrays.
+
+## Installation
+
+    $ npm install array-difference
+
+## Usage
+
+    var array1 = [1, 2, 3];
+    var array2 = [2, 3, 4];
+    difference(array1, array2); // yeilds [1, 4]
+
+## License
+
+Copyright (c) 2013 [Mike Pennisi](https://github.com/jugglinmike)  
+Licensed under the MIT Expat license.