Help me to understand functors

Feel free to make a pull request against the markdown file! (If you don’t want to, file an issue? I’m not in a position to log the problem right now.)

Thanks to coloration, I realized that I forgot to put the type annotation on the empty value in the signature.

I’m fine with then new wording.

Indeed, this implementation is simpler and clearer.

Please do a pull request, or a github issue. :slight_smile:

I managed to get a minute to do the things above. Someone check if I got them right.