On: Covariance and Contravariance

[gclaramunt]

I think is just a matter of editing, the line "It even works with functions:" should probably say something like "It's even the same with functions" as before clearly stated that "let cat: Cat = Animal()" doens't work

[mikeash → gclaramunt]

"Editing"? You overestimate me. Anyway, thank you both for pointing this out, I've improved (I hope) the wording now.