A basic program written in the Dart programming language

main.dart

class Person {
  String _name;
  int _age;
  String occupation;
  List<String> hobbies;
  
  Person(this._name, this._age, [ this.occupation, this.hobbies ]);
  
  String getIntro() => 'Name: $_name. Age: $_age. Occupation: $occupation';
  
  String getInterests() {
    if (this.hobbies == null) return '$_name has not listed any hobbies :-(';
    var interests = '';
    
    for(var i = 0; i < hobbies.length; i++) {
       if (i == hobbies.length - 1) {
         interests += 'and ${hobbies[i]}';
       } else {
         interests += '${hobbies[i]}, ';
       }
    }
    
    return interests;
  }
}

main() {
  Person john = new Person('John Doe', 25)
  	..occupation = 'Doctor'
    ..hobbies = ['Singing', 'Biking', 'Travelling'];
  
  print(john.getInterests());
}