title: Can I observe additions to an array with rx.js?
body: <p><a href="https://github.com/Reactive-Extensions/RxJS/wiki/Observable#wiki-fromArray" rel="noreferrer">fromArray Rx wiki on github</a></p>
  
  <pre><code>coffee&gt; rext = require 'rx'                                                 
  coffee&gt; arr = [1..5]                                                 
  [ 1, 2, 3, 4, 5 ]                                                    
  coffee&gt; obs = rext.Observable.fromArray(arr)                         
  { _subscribe: [Function] }                                           
  coffee&gt; obs.subscribe( (x) -&gt; console.log("added value: " + x))      
  added value: 1                                                       
  added value: 2                                                       
  added value: 3                                                       
  added value: 4                                                       
  added value: 5                                                       
  { isStopped: true,                                                   
    observer:                                                          
     { isStopped: true,                                                
       _onNext: [Function],                                            
       _onError: [Function: defaultError],                             
       _onCompleted: [Function: noop] },                               
    m: { isDisposed: true, current: null } }                           
  coffee&gt; arr.push(12)    # expecting "added value: 12"                                              
  6                       # instead got new length of array                                              
  coffee&gt;          
  </code></pre>
  
  <p>It really looks like the <code>subscribe</code> function will only fire one time, when it's created. It seems like it's a bit of a misnomer, since I'm really just for-eaching the array instead of observing changes on it. That code is almost exactly the same as what's on the wiki though. So either I'm doing it wrong or the <code>subscribe</code> doesn't work how I expect. </p>