Pattern matching 6

readme.md

Pattern matching 6

Created with <3 with dartpad.dev.

main.dart

@sealed
abstract class _CarPart {
  Engine(int cylinders, int horsepower);
  Transmission(int gears, bool isManual);
}

class Car {
  const Car(
    this.model, {
    required this.parts,
  });
  final String model;
  final List<CarPart> parts;

  String get description => [
        'These are the parts in a $model:',
        for (final part in parts) '- ${_getDescriptionForCarPart(part)}',
        '- And a whole bunch of other parts which I was too lazy to mention.',
      ].join('\n');
}

String _getDescriptionForCarPart(CarPart part) => part.when(
  engine: (v) => 'A ${v.cylinders} cylinder engine '
        'which makes ${v.horsepower}hp.',
  transmission: (v) => 'A ${v.gears} speed '
        '${v.isManual ? 'manual' : 'automatic'} transmission.',
);

void main(List<String> args) => print(
    const Car(
      'Nissan Skyline GT-R',
      parts: [
        CarPart.Engine(cylinders: 6, horsepower: 300),
        CarPart.Transmission(gears: 7, isManual: true),
      ],
    ).description,
  );