Thank you SO much, @MargaretJLake (and Margaret’s Granny!)…embroidered lab coat might just be the best win so far….not to mention the amazing job @MargaretJLake did on her first surgeries today!! Super proud and grateful!!🎉🤓🥰❤️
OK, with that in mind, let's revisit the type of the function we want to write:
forall (l1 l2 : list T),
length l1 = m ->
length l2 = n ->
length (append l1 l2) = m + n
What does it do? Well, it will take in two lists as arguments. So let's modus ponens that shit.