## Oh no! Animated Alligators!

Lambda calculus as animated alligators and eggs. Virtually guaranteed to turn any 4 year old into a PLT geek.

The non-animated game was mentioned previously on LTU here.

## Comment viewing options

### VEX

I saw that the package, DiaMeta, supports another visual representation of the lambda calculus, VEX: Wayne Citrin, Richard Hall, Benjamin Zorn, 1995; Programming with Visual Expressions, Proc. Visual Languages '95.

I wonder if a hybrid of the two might give a more pleasingly spatial version of alligator eggs?

Postscript— I saw that Steffen Manazek had a blog post about VEX.

### foundational questions

No, I'm sorry, I have difficulty accepting this.

When I was in elementary school and we were being taught about ">" and "<" the instruction was very clear -- "<" and ">" are like alligators with open mouths facing in opposite directions and, being alligators, they always face the direction of the larger supply of food. The re-use of alligators in this lambda calculus concept simply conflates notations and risks confusing fundamentally distinct concepts. I can only conclude that the author, like so many who have accents different from mine, has a kind of nihilistic postmodern sensibility. He is probably one of those "Social Text" vandals. Whatever it is, I suspect he has set the field of study back by at least several decades. Think of the children! Won't someone please think of the children?!?

-t

p.s.: In truth it might be interesting to see, say, a lambda calculus implementation of a tower of hanoi solver. I haven't written a lambda calculus version of such a thing so I'm just speculating but I speculate that the familiar physical form of the puzzle would be recognizable in a tree representation of corresponding lambda forms. You could build up from animations of a small number of alligator-and-egg examples ((not false) and true) and eventually zoom out to a many-element animation that not only solves the tower of hanoi problem but, while it does so, looks like it is doing so....

And, y'know.... that'd be cool and stuff.

### (\x.(x x) \x.(x x))

I was rather hoping to see a mesmerizing dance of alligators forever consuming one another. And some automated parallelization would have been nice, even if it was limited based on the number of animations that can be handled at once.

Next step: artificial-life programming languages!

Or maybe a visual interpretation of Inform 7... I think children could learn that.

### @alligators forever consuming one another

i think Camille Paglia had a story like that. oh. wait.