Are those programmers Java or C# programmers? I'm not an OOP expert, but I get the impression that type classes are similar to interfaces in Java and C#, which

Are those programmers Java or C# programmers? I'm not an OOP expert, but I get the impression that type classes are similar to interfaces in Java and C#, which are used all the time in those languages. If you told a C# programmer that IEnumerable was an example of bad architecture, I think you may get a somewhat different response.