Here's the context I'm asking about:
"My dad was funny. That was one of the reasons all of my childhood and college friends loved him (and man did they love him)”.
I understand that "did they love him" here is an exclamation rather than a question. It means "wow, they really loved him”, or does it mean something else?
Also, is there a name for this grammatical rule? I couldn't find anything on google and I want to learn more about it.