I'm not looking for a single sentence explanation or definition. I'm willing to read more, and the structure you suggest of showing precisely worded definitions along with positive and negative examples would be great! However, I would not want to start with reading how to install a compiler, how to add two numbers in Haskell, etc.
I have similar issues elsewhere when people start with hello worlds and getting started in introductions to projects and programming languages without spending enough time on what the thing is about.
Similarly, you may know what eigenvector, or derivative function, is, but without practice you can't understand why you may want it.