TDPL question: "objects may not embed internal pointers", classes too?

[Adam D. Ruppe]

On page 249 of TDPL (Andrei's book), in a section on structs and 
postblits, it says "D objects must be relocatable" and other 
similar statements while banning internal pointers.

I knew this applies to structs and the context makes that plainly 
clear, but the word "object" is a bit ambiguous: does this apply 
to classes too?