Editing Arrays

Arrays are a good way to handle lists of things.  In JavaScript, Arrays use the square brackets [ and ] 

To create an Array, all you need to do is assign the list to a variable 
<pre>
   var m = [3,6,8];
</pre>

To access individual items of the list you use the square brackets again.
<pre>
   var p = m[1]; 
</pre>

Entries in the list start counting from zero so <tt>m[0]</tt> is the first item in the list.    <tt>[2]</tt> accesses the item at position 2 but it is important to remember that position 2 is the third item in the list.   If you are new to programming, this might seem a bit odd at first.  don't worry, it doesn't take too long to adjust to counting from zero.

<edcode>
var names = ["Jane","Pete","Bruce","Bella"];
var someNumbers = [5,7,9,1,3,3,3,4];

print("The arrays are");
print(names);
print(someNumbers);

print("Arrays start counting at zero so their first item is accessed by [0]",0,150);
print(names[0]);
print(someNumbers[0]);

print("Their third item is [2] ",0,300);
print(names[2]);
print(someNumbers[2]);

</edcode>

You can also add items to lists.  The <tt>push</tt> function is available to add items to the 
<edcode>
var fruits = [];
fruits.push('banana', 'apple', 'peach');

print(fruits);

print("there are " +fruits.length+ " fruits"); 
</edcode>



The mozilla foundation has documentation on Javascript Arrays at https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array

In additon to the standard features of Arrays available to JaveaScript users,  Code on this wiki has been sweetened with SugarJS 
The additional features are documented at http://sugarjs.com/api/Array 

SugarJS allows some cool abilities like <tt>exclude</tt>

<edcode>
var fruits = [];
fruits.push('banana', 'apple', 'peach');

fruits = fruits.exclude('apple');

print(fruits);

print("there are " +fruits.length+ " fruits"); 
</edcode>