SICP

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λ interpreter 200ms

Run speed 200ms

Run max depth During Run, step into calls until this trace depth. Deeper recursive calls are evaluated with Step Over, keeping the final fold and side-effect notes without rendering every similar frame. Use Unlimited for the old fully step-in run.

Trace detail All renders the full substitution trace. Marks keeps Run abridged by expanding calls reached through break or tap marks, plus notes and final folds.

Marks

idle

No history yet.

No canvas output yet.

Break pauses Run at a match. Tap logs a note and makes that call expand when trace detail is set to marks. Watch records hits and latest values without changing the trace. trace

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deps

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Use this panel as a reference for the reader controls. It is the durable replacement for a popup tutorial.

Reading and Navigation. Forward and back move through reading steps inside a section. At section boundaries, a deliberate pull or button press turns the page. The breadcrumb arrows move by subsection. Contents moves by chapter, section, or subsection. The double-arrow button appears when you have a saved furthest point; right-click it to reset that marker to the current step.

Search and Reference. Search indexes prose, headings, exercises, and Scheme definitions. Index follows the original back-of-book terms and jumps to their first useful occurrence when possible. Definitions groups Scheme names by chapter and section, with dependency filtering for names used by the current section.

Exercises and Checkpoints. Checkpoint cards ask for short predictions or code runs at points where a small pause helps the reading. Exercise cards keep starter code and attempts in local storage under this browser profile. Optional exercises start collapsed, so they stay visible in the flow without forcing every reading session to become a problem set.

Interpreter Panel. The lambda button opens the Scheme panel. Run evaluates continuously; Step and Step over expose smaller evaluation moves. Editor scope follows the current section. Scratch can be section-local or global. The Canvas tab is used by picture-language examples when a program produces painter output.

Display, Storage, and Sources. Theme, skin, code size, keymap, Parinfer mode, and exercise strictness live in Settings. Progress, exercise attempts, scratch buffers, and panel state are stored locally in the browser. Book text comes from the MIT HTML edition; modernized figures and typography are credited to sarabander's SICP edition.