Didactic

Didactic: (from the Greek,"teaching") A term used to describe a work that teaches a specific lesson or moral or provides a model of moral or ethical behavior or thinking.

Example:
" It was fifteeen minutes before I could work myself up to go and humble myself to a nigger- but I done it, and warn't ever sorry for it afterwards, neither. I didn't do him no more mean tricks, and I wouldn't done that one if I'd knowed it would make him feel that way."
           (Huckleberry Finn, Pg.87)

This is a good example of a didactic situation because he's teaching us a lesson. He's trying to tell us that there is no difference is apologizing to a black person from apologizing to a white person. He says that he wasn't sorry for it and therefore we shouldn't eather. (During that time)