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# Prototype Array Processing

Prototype extends all native JavaScript arrays with quite a few powerful methods.

This is done in two ways:

- It mixes in the Enumerable module, which brings a ton of methods in already.

- It adds quite a few extra methods, which are documented in this section.

## Using Iterators:

One important support provided by Prototype is that you can use java like iterator in JavaScript. See the difference below:

Traditional way of writing a for loop:

    for (var index = 0; index < myArray.length; ++index) {
      var item = myArray[index];
      // Your code working on item here...
    }

Now if you are using Prototype then you can replace above code as follows:

    myArray.each(function(item) {
      // Your code working on item here...
    });

Here is the list of all the functions with examples dealing with Array.

# Prototype Array Methods:

NOTE: Make sure you have at least version 1.6 of prototype.js.

Methods | Description
--- | ---
clear() | Clears the array (makes it empty).
clone() | Returns a duplicate of the array, leaving the original array intact.
compact() | Returns a new version of the array, without any null/undefined values.
each() | Iterates over the array in ascending numerical index order.
first() | Returns the first item in the array, or undefined if the array is empty.
flatten() | Returns a "flat" (one-dimensional) version of the array.
from() | Clones an existing array or creates a new one from an array-like collection.
indexOf() | Returns the position of the first occurrence of the argument within the array.
inspect() | Returns the debug-oriented string representation of an array.
last() | Returns the last item in the array, or undefined if the array is empty.
reduce() | Reduces arrays: one-element arrays are turned into their unique element, while multiple-element arrays are returned untouched.
reverse() | Returns the reversed version of the array. By default, directly reverses the original. If inline is set to false, uses a clone of the original array.
size() | Returns the size of the array.
toArray() | This is just a local optimization of the mixed-in toArray from Enumerable.
toJSON() | Returns a JSON string.
uniq() | Produces a duplicate-free version of an array. If no duplicates are found, the original array is returned.
without() | Produces a new version of the array that does not contain any of the specified values.

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