Dartfactory构造函数语法问题

class Father {

  String name;

  Father(this.name);

  // 下面两行，是等效的吗？是什么语法，官方文档具体页面有没有？

  factory Father.born(String name) = Son;

  factory Father.born2(String name) => Son(name);

}



class Son extends Father {

  Son(String name): super(name);

}





main(List args) {

  var son1 = Father.born('name1');

  var son2 = Father.born2('name2');

  print(son1.name);

  print(son2.name);

}