§ Stalking syzigies on hackernews

He's the author of Macaulay; I learnt quite a bit by stalking him on hackernews - Lisp's signature 17 car pileup at the end of every expression.
  • I look for the $ or equivalent in any proposal out there, to see if theauthor has written lots of code or is just talking. It's like looking forbone marrow in beef stew, evaluating a cookbook. Marrow is central to thestory of Lisp; we got our start being able to wield tools to crack open bonesafter lions and jackals had left a kill. The added nutrition allowed ourbrains to increase in size. Soon we mastered fire, then Lisp.
  • I spent the first few months outside doing woodworking; I've been strugglingwith an overwhelming urge to center my consciousness in my hands. This is ofcourse the history of our species, a biological urge as profound as our sexdrive. We figured out how to make very sharp hunting tools from unrulyrocks, or we died.
  • The first chapter of Berstel and Reutenauer's "Noncommutative RationalSeries with Applications" presents Schützenberger's theorem that everynoncommuting rational power series is representable, and conversely. Theidea is NOT painfully abstract, but makes twenty minutes work of a semesterof undergraduate automata theory (an assertion I've tested multiple times inmy math office hours).
  • You don't want sync software going off and "thinking" about what a symlinkreally means, anymore than you'd want sync software going off and "thinking"after finding porn on your computer
  • Luckily, I was trained far enough down the street from MIT to escape theirLisp world view, so we coded our computer algebra system in C, and it wasfast enough to succeed and bring us tenure. Today, we'd choose Haskell.
His LISP language with inferred parens:
define | edge? g e
    $ es | edges g
      e2 | reverse e
    or (member e es) (member e2 es)
(define (edge? g e)
    ( (es (edges g))
      (e2 (reverse e)))
    (or (member e es) (member e2 es))))