How to distinguish the class member from global variable with the same name in Dart?

I am trying the following code:

String user() {
  return "";
}

class Foo {
  String user;
  Foo() : user = user(); // <= error here
}

void main() {}

But it doesn't work because of name ambuguity.

I can move globals to another module and import as globals to avoid it.

Is there any other way?

The Dart lexical lookup, used to give meaning to plain identifiers, stop at the first scope level which contains a member with that name. Qualified identifiers, the bar in foo.bar, are not looked up lexically, so they do not have the same issue.

You need to provide a way to access the outer name using either another plain name, or using a qualified name.

The other plain name is the easier way:

String user() {
  return "";
}

String _user() => user(); // Add redirect with other name
// or `const _user = user;` to create a tear-off.

class Foo {
  String user;
  Foo() : user = _user(); // <= No error now
}
void main() {}

Adding a prefix for a top-level name is slightly harder. If it's an imported name, also import the same library with a prefix:

import "other.dart"; // provides `user`
import "other.dart" as other; // access also as `other.user`
...
  : user = other.user() ...

If the member is declared in the same library, then the solution is the same: Import the library with a prefix. It just feels a little more weird to import the current library into itself, but it's perfectly fine and valid Dart.

library my_library;
import "my_library.dart" as self;
String user() => ...
// ...
   ...: user = self.user() ...

It's only top-level names that have this issue. Static or instance members can be accessed with a qualified identifier using ClassName.staticMember or this.instanceMember, without needing to introduce a new prefix name.