[Flutter] How to create a generic factory with injectable in Dart/Flutter?

I'm trying to come up with a scalable solution for factory registration in Dart/Flutter using injectable (or any other DI library).

Currently, I explicitly create a factory class (BarFactory) for each type (Bar), and call their create method (in Foo.doSomething) to create the instance (Bar):

import 'package:injectable/injectable.dart';

@singleton
class Foo {
final BarFactory _barFactory;

Foo(this._barFactory);

void doSomething() {
var bar = _barFactory.create();
bar.blah();
}
}

@injectable
class BarFactory {
Bar create() => const Bar();
}

@injectable
class Bar {
const Bar();

void blah() {
/* ... */
}
}


The above dicatates writing a BarFactory for each Bar type. I can of course call getIt.registerFactory(() => Bar()) explicitly, but that's not much different from the above.

I tried to create a generic factory like this:

@injectable
class Factory<T> {
final T Function() create;
const Factory(this.create);
}


but that results in this error:

[SEVERE] injectable_generator:injectable_builder on lib/temp.dart:

Can not resolve function type
Try using an alias e.g typedef MyFunction = T Function();


which doesn't even make sense as T is a type parameter...

Any ideas on how to achieve this? I'm open to using a different DI library if it helps.

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