在命名参数中=和：之间的Dart差异

Question

class Student {
  String name;
  int age;
  int id;

  Student({this.name, this.id = 101, this.age: 20});
}

What is the difference between = and : in above constructor? Both seems to do the same job.

Answer 1

From the documentation:

Deprecation note: Old code might use a colon (:) instead of = to set default values of named parameters. The reason is that originally, only : was supported for named parameters. That support is likely to be deprecated, so we recommend that you use = to specify default values.

Source: https://dart.dev/guides/language/language-tour