uniq :: Array

uniq() -> newArray Produces a duplicate-free version of an array. If no duplicates are found, the original array is returned.

Example

['Sam', 'Justin', 'Andrew', 'Dan', 'Sam'].uniq();

// -> ['Sam', 'Justin', 'Andrew', 'Dan']

['Prototype', 'prototype'].uniq();

// -> ['Prototype', 'prototype'] because String comparison is case-sensitive

Performance considerations

On large arrays with duplicates, this method has a potentially large performance cost:

· | Since it does not require the array to be sorted, it has quadratic complexity.

· | Since it relies on JavaScript’s Array.concat, it will yield a new, intermediary array every time it encounters a new value (a value that wasn’t already in the result array).

More efficient implementations could be devised.

This page will get updated if such an optimization is committed.

Prototype API 1.5.0 - prototypejs.org