instanceOf<T extends Object> static method

T instanceOf<T extends Object>(SingletonInstanceCaller<T> caller)

Singleton class like:

class A { A._(); // Private constructor

static A get instance => Singleton.instanceOf(() => A._()); }

Implementation

static T instanceOf<T extends Object>(
  SingletonInstanceCaller<T> caller,
) {
  return _proxies[T] ??= caller.call();
}