Polymorphism

movement.dart

class Movement {
  String get status => 'COMPLETED';
  
  bool get isForeignCurrency => false;
}

class Deposit extends Movement {}

class Charge extends Movement {
  String status;
  
  Charge({this.status});
  
  bool get isForeignCurrency {
    // if originalAmount…
    return true;
  }
}

void main() {
  // From JSON, without status
  final deposit = Deposit();
  // FROM JSON, with status
  final charge = Charge(status: 'PENDING');
  
  print(deposit.status); 
  print(charge.status);
  
  print(deposit.isForeignCurrency);
  print(charge.isForeignCurrency);
}