plain-grass-6880

readme.md

plain-grass-6880

Dart Quiz

Does the order of the superconstructor call in the initializer list changes the invocation order of the superclass constructor and other initializers?

In other words in which order the code will be executed? Pick the right answer:

1. B#super, A#ctor, B#bar, B#ctor
2. B#bar, B#super, A#ctor, B#ctor
3. B#super, B#bar, A#ctor, B#ctor
4. B#super, B#bar, B#ctor, A#ctor

Find the runnable version here.

Created with <3 with dartpad.dartlang.org.

main.dart

class A {
  final foo;
  A(this.foo) {
    log('A#ctor');
  }
}

class B extends A {
  final bar;
  B()
      : super(log('B#super')),
  		  bar = log('B#bar') {
    log('B#ctor');
  }
}

class C extends A {
  final bar;
  C()
      : bar = log('C#bar'),
  			super(log('C#super')) {
    log('C#ctor');
  }
}

/// Stopwatch to timestamp the log messages.
final sw = new Stopwatch();

/// Prints the [label] with a timestamp next to it.
log(String label) => print('${label.padRight(7)}: ${sw.elapsedTicks}');

main() {
  print('Experiment 1\n');
  sw.start();
  new B();

  sw..stop()..reset();
  
  print('\nExperiment 2\n');
  sw.start();
  new C();
}