Feature request: service lookup & Singleton

[kcmvp]

1: Does this framework ensure singleton instance?

2: Support service lookup:
There is scenario that we just want to get a service when in a function call but I dont want to new a new instance of the target service.

in java ecosystem the famous springboot support above features.

I am choosing a DI framework for my project and find I need above two features. the case is

** source code**

interface A {
  M1()
  M2()
}
var _ A = (*ImplA)(nil)
struct ImplA {
}

func NewImplaA() {
}
....

but right now I want to test another function which depends on the interface(ImplA) with Mock. if this framework can supply above features than I can inject a mocked implementation and then the tested method can looup the mock object.

[samber]

1- You can call Invoke[ImplA](injector) many times, and the same instance will be returned (singleton)
2- See https://github.com/samber/do#cloning-injector