Cannot use int type with the sortedBy API

[etiennestuder]

Using Dart 3.2.4 and the collections package, and writing the code below...

['alpha','beta'].sortedBy((element) => element.length);

I get the error printed below:

Error: Inferred type argument 'int' doesn't conform to the bound 'Comparable<K>' of the type variable 'K' on 'IterableExtension|sortedBy'.
 - 'Comparable' is from 'dart:core'.
Try specifying type arguments explicitly so that they conform to the bounds.
    var xx = ['alpha','beta'].sortedBy((element) => element.length);

Does it mean that int does not implement Comparable?
I did not know how to apply the advice given in the error message.

I'm not a Dart expert, and it is unclear to me whether sorting by a criteria of type int is not supported by design when using the sortedBy API, or if I'm doing something wrong, or if there is an issue in the library.

[etiennestuder]

I found the following issue and solution:

['alpha', 'beta'].sortedBy<num>((element) => element.length);

[eernstg]

Note that the example works with Dart 3.7.0 and up because inference was generalized to use bounds more effectively:

import 'package:collection/collection.dart';

void main() {
  print(['alpha', 'beta'].sortedBy((element) => element.length));
}

[etiennestuder]

Cool. Thanks for the heads-up, @eernstg.