Ember.isNone()

Returns true if the passed value is null or undefined. This avoids errors from JSLint complaining about use of ==, which can be technically confusing.

Ember.isNone();              // true
Ember.isNone(null);          // true
Ember.isNone(undefined);     // true
Ember.isNone('');            // false
Ember.isNone([]);            // false
Ember.isNone(function() {}); // false