It's official. I am a total gumby. There are minds out there that are to mine as the entire city of New York is to a house brick and half a bagel. And they're all using APL.
I'm quite amazed how the author has not made any mistake in the presentation. I wonder if using APL leads to a different state of mind where tool is out of your way or was it simply a well rehearsed demo?
My prof also writes complex APL code live and I've never seen a program he made that didn't run or had a bug. He has a I ❤ APL sticker on his laptop. And he is a god damn genius, we can't compare us to him in absolutely no, no way. It doesn't lead to a different state of mind, that guy was already born a genius a little like rainman, but without the downsides.
He switched to J after I showed him that a few years ago and is ever happy since. He told me that he paid about 2000bucks for his APL compiler back then.
Nonetheless, because array programming requires unorthodox input and is sufficiently different than popular paradigms, authors typically write slower which may explain the deliberateness.