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In the following DOM event handling example (using jQuery):

$('#shopping-cart').on('click', function(event){...});

could I not call the shopping-cart DOM element the observable, and the function the observer? There is no "general" click event being hooked to, but a click event specific to the shopping-cart object itself.

The javascript example of observable/observer example I'm operating from is the following (taken from here):

// MyFancyObservable.js
var util = require('util');  
var EventEmitter = require('events').EventEmitter;
function MyFancyObservable() {  
  EventEmitter.call(this);
}
util.inherits(MyFancyObservable, EventEmitter);
MyFancyObservable.prototype.hello = function (name) {  
  this.emit('hello', name);
};


var MyFancyObservable = require('MyFancyObservable');  
var observable = new MyFancyObservable();
observable.on('hello', function (name) {  
  console.log(name);
});
observable.hello('john');  

Notice that in the MyFancyObservable example, the on('hello', function) looks exactly like DOM event registration.

1

The difference lies in the purpose of the Event.

In your Shopping Cart example, the event gets fired in response to a user action.

In an Observable, the event gets fired in response to a state change.

Are they both examples of Event Handling? Yes.

Are they both Observers? No.

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