What is the difference between angular.copy() and an assignment (=)?

= represents a reference whereas angular.copy() creates a new object as a deep copy.

Using = would mean that changing a property of contextwould change the corresponding property of $scope.master or vice versa.

Using angular.copy() the two objects would remain seperate and changes would not reflect on each other.

As can be read here angular.copy() performs a deep copy (cf. "clone") of the argument - essentially creating a new object - whereas using the assignment operator = just assigns reference's.

Thus in the latter case, if you we're to change something in $scope.master you would also change context.

Cheers,