Planes

a language that shows its work

Planes is a small programming language you can read aloud. It answers two questions most languages cannot: what would this program touch in the outside world — computed by reading it, never by running it — and where did this value come from, for any value, all the way back. It has two independent implementations, in Python and in JavaScript, that are checked against each other on every change. Its numbers are exact. Nothing below is compiled, bundled or transpiled: these pages fetch the real source and run it.

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a crossing A seeded Passage through Ala Eriri — visual, playable, moving, musical, and granular enough to explain any mark you select.

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the garden A scene that lives — a day and night, weather, plants that grow, and music in exact ratios. Click any mark and it tells you where it came from.

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paint The same language, drawing: turtle, bloom and snake. One program, two renderers — a canvas and an SVG file that agree.

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try it Write Planes and run it here, with nothing installed. Then ask what it would touch, without running a line of it.

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planes on planes A Planes interpreter written in Planes, running on the JavaScript one. The same program, both ways, compared — and what the second layer costs.

Source, specifications and the test gate: github.com/rmichaelthomas/planes. These pages are static files — serve the folder with python3 -m http.server and open it, or read them from the repository. There is no build step anywhere in this project.