angular.copy vs angular.extend

angular.copy and angular.extend 차이점.

angular.copy provides a deep copy:

var src = {foo: "bar", baz: {}};
var dst = angular.copy(src);
console.log(dst.baz === src.baz); 
// "false", it's a deep copy, 
// they point to different objects.

angular.extend provides a shallow copy:

var src = {foo: "bar", baz: {}};
var dst = {};
whatever.extend(dst, src);
console.log(dst.foo);             // "bar"
console.log(dst.baz === src.baz); 
// "true", it's a shallow copy, both
// point to same object