Set and return variable in one line in dart?-CodePudding

I think I remember something like this from python, maybe it was the walrus operator? idk.

but is there a way to set an attribute while returning the value? something like this:

class Foo {
  late String foo;
  Foo();
  String setFoo() => foo := 'foo';
}

f = Foo();
x = f.setFoo();
print(x);
// 'foo'

CodePudding user response：

I think I found it, that is, for the case that foo can be null:

class Foo {
  String? foo;
  Foo();
  String setFoo() => foo ??= 'foo';
}

CodePudding user response：

Nobody forbids you to do it just like you said:

class Foo {
  late String foo;

  String setFoo() => foo = 'foo';
}

void main() {
    print(Foo().setFoo());
}

The only drawback of using the late modifier is that you can accidentally access the foo field before the initialization, which will cause a LateInitializationError. To prevent this, you can use a nullable type for the field.

Moreover, you can just initialize the field inline:

String foo = 'foo';