I have recently found the following code on the Ionic codePen:
$scope.add = function() {
var nextMessage = messageOptions[messageIter++ % messageOptions.length]; // some string
$scope.messages.push(angular.extend({}, nextMessage));
}
Why did the developer used angular.extend({}, nextMessage) as an input parameter of to javascript push function instead of directly passing the nextMessage as an argument?
It is used to create a copy nextMessage object and push that copy to the array.
Extends the destination object dst by copying own enumerable properties from the src object(s) to dst. You can specify multiple src objects. If you want to preserve original objects, you can do so by passing an empty object as the target: var object = angular.extend({}, object1, object2).
Javascript's Array.push() method will push items, not extend arrays.
var array1 = [1, 2, 3, 4];
var array2 = ['a', 'b'];
array1.push.apply(array1, array2);
console.log(foo); // will output [1, 2, 3, 4, "a", "b"]
angular.extend() method will extend arrays/objects, not push items.
var array1 = [1, 2, 3, 4];
var array2 = ['a', 'b'];
angular.extend(array1, array2);
console.log(foo); // will output ["a", "b", 3, 4]
