Interfaces How implicit interfaces work in Dart

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An interface is a contract that a class must follow. Prefixing a method or variable with _ makes it private, so it won’t be visible when imported from a different file.

file_type_dartlang interfaces.dart
class Elephant {
  // Public interface
  final String name;

  // In the interface, but visible only in this library. (private)
  final int _id = 23;

  // Not in the interface, since this is a constructor.

  // Public method.
  sayHi() => 'My name is $name.';

  // Private method.
  _saySecret() => 'My ID is $_id.';


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