Duck-Typing in Dart with implements
Interfaces are programming language constructs that describe at a high level how classes will behave. That is, if a class implements an interface, it must define the methods and instance variables that are declared in the interface.
In Dart, everything is an interface, which is another way of saying that there are no explicit interfaces. Any class in Dart—abstract or concrete—is a potential interface. Our ComicsCollection class could implement the built-in Iterable abstract class.
| classes/implements.dart | |
| | class ComicsCollection implements Iterable { |
| | void forEach(fn) { |
| | models.forEach(fn); |
| | } |
| | |
| | int get length => models.length; |
| | // ... |
| | } |
What this tells other Dart classes is that there is ...
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