Kartik Agaram

04/17/2023, 2:28 AM
Befunge, but readable made the rounds of the internet yesterday, and caused me to swap in an old interest of mine that I've flailed ineffectually at in the past (e.g. a way to display a program that makes its large-scale structure really obvious (rather than obfuscating it as Befunge does). One problem I have with Befunge (not the one you're thinking of, ha) and other fungeoids [1] is that you have a bunch of static information about a program visible in 2D on screen, but a key piece -- the stack -- is invisible. The question I keep returning to is how one might go about making the stack (or any other run-time state used by the program) visible without just bolting it on on the side. This time around, I got hooked on the following metaphor. Imagine a spaceship that contains some data, sets out on a voyage across an infinite 2D plane, and performs various operations depending on the objects it collides with. Example 1: The space ship contains a row of boxes. Colliding with a number pushes a box on to the nose, colliding with an operator operates on the 1 or 2 front-most boxes in the front. This is a way to display a stack, but a stack in isolation doesn't seem to scale well to larger programs. Example 2: The spaceship contains a number. Colliding with the BF-inspired primitives
[2] causes the number to be incremented and decremented, respectively. Now build addition out of it. Zooming into a number
shows it to be a loop of n iterations. When the spaceship collides with
it loops through n times, and the number inside it has n added to it. At a high zoom, you see the spaceship loop n times before exiting the "solar system". At a low zoom you see the spaceship exit instantaneously with n added to its value. Now you can imagine a reduce operation as a series of solar systems that the spaceship visits one by one. Example 3: The spaceship contains a binary heap to insert and delete elements from depending on objects it collides with. Zooming into any single collision reveals the tree structure to be the "space" that a smaller spaceship containing a single number bounces among. Two properties that seem important from these examples: • A hierarchical nature where space and spaceship are duals, and zooming in and out causes them to turn into each other. • Rendering the state of a spaceship needs to be extensible[3]. We need to leave Befunge's ASCII behind. At the largest scale, state machines feel like a really powerful way to represent the state within a spaceship. I often find them to be the outermost architecture of a large program. But to actually find the state machine I have to flail around for a long time. If we could use some visual paradigm at the largest scales but zoom into text as needed, programs might be much more comprehensible. [1] [2] [3] Like in my old Pong demo:


04/17/2023, 11:24 AM
“... A hierarchical nature ...” FWIW, I strongly agree with this phrase. A minor change in POV might make this whole problem simpler... We need notations that embrace hierarchy and relative-ism. Lisp lists, UNIX relative pathnames, StateChart nested machines, Kinopio “/”, HTML links, Dave Ackley all swirl around this flame... Force-fitting 4D reality down into a single 2D notation causes self-imposed accidental complexity (epicycles). We need to be thinking in terms of trees of stacks, trees of CPUs/machines/phones, trees of messages, etc.