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• Why Dart does not inherit constructor?
• inheritance - How do I call a super constructor in Dart?

• Redirecting/Forwarding Constructors (search in ch02)

  class Point {
    num x;
    num y;
  
    Point(this.x, this.y);                // The main constructor for this class.
    // A redirecting constructor’s body is empty, with the constructor call appearing after a colon (:).
    Point.alongXAxis(num x) : this(x, 0); // Delegates to the main constructor.
  }
  

• Redirecting Factory Constructors

  class Foo {
    Foo(int a, int b) { … }
    Foo.named(int c, int d) { … }
  }
  
  class Bar extends Foo {
    Bar(int a, int b) : super(a,b);
  }
  
  class Baz extends Foo {
    Baz(int c, int d) : super.named(c,d);  
  }
  
  
  // factory TemplateCache() = LruCache<String, HttpResponse>;
  

• Calling a superclass method

  class Foo {
    f() {
      print("foo");
    }
  }
  
  class Bar extends Foo {
    f() {
      super.f();
      print("bar");
    }
  }