I tried with this but it doesn't work. Foo is just a test of what works. Bar is the real try, it should receive any newable type but subclasses of Object isn't valid for that purpose. class A { }...

When writing code we should be able to identify two big group of objects: Injectables Newables http://www.loosecouplings.com/2011/01/how-to-write-testable-code-overview.html http://misko.hever...

Assume you divide up your systems in Value objects and Services objects (as suggested in "Growing Object-Oriented Software, Guided by Tests". Misko Hevery calls these "newables" and "injectables". ...