Hydra Metacircular Evaluator

A live embedded demo where each Hydra sketch illustrates one clause of the evaluator: literals, lookup, quotation, branching, closure capture, application, sequencing, and recursion.

camera = expression stream

o1-o3 = environment / side buffers

mask = dispatch / branching

feedback = self-application

Start

The camera needs a user gesture. After that, the scene buttons below can be used freely.

Scenes

Reading guide

self-evaluating? keeps the image almost untouched.

variable? consults another texture, so meaning comes by indirection.

quoted? reduces motion and semantic transformation.

if? splits the visual field into two branches via a threshold mask.

lambda? captures a side-buffer that keeps acting later, like a closure.

application appears as one texture modulating another.

begin? stages the image through several buffers in order.

Y / recursion routes output back into input with feedback.

Scene not started

Awaiting camera permission

Concept

Press Start camera + scene 1 to begin the embedded demo.

Concept

Current Hydra code