[dem-extra1]

Requested by Ezra · project thread

Important

Stacked on #139, which adds the racket engine. Merge #139 first; this PR's base then moves to main.

Part of #131.

Why

The chapter typed what each Racket call returns, so nothing checked the values against the code.

What changes

In the first half of chapters/functional-programming.qmd, up to exr-twice:

• the chapter includes _subfiles/_racket-setup.qmd, which registers the engine;
• each fence that defines a function (h, ticket-price, absolute, twice, add-three) is a {racket} chunk with code-fold: false;
• exm-absolute-value shows (absolute -7) and (absolute 2) as chunk output instead of typing 7 and 2;
• the solutions to exr-evaluate-nested, exr-formula-from-code, exr-ticket-price and exr-twice keep their worked reasoning
  and end with "Racket returns the same values:" and a chunk that runs the same expressions.
  The exercises show only definitions, so no chunk output gives away an answer before its solution.

The syntax templates in def-racket-define and def-if-cond ((define (f x1 ... xn) body)) are not runnable,
and the evaluation traces in rem-evaluation and exm-substitution are hand rewriting steps, so they stay plain fences.
The prose inside definitions (def-booleans) still states a value inline; I left definitions alone.

The second half is #141, stacked on this one, because the two together exceed the 10-file cap.

Testing

Rendered the chapter to HTML and to revealjs locally with Racket 8.10. Every chunk's output matches the value the prose and solutions state:
(* (+ 1 2) (- 10 4)) 18, (- 20 (* 3 (+ 1 1))) 14, (+ 1 2 3 4) 10, (- (* (+ 2 3) 4) 1) 19,
(h 5) 15, (h (h 3)) 3, ticket-price 0, 8, 8, 12, absolute 7 and 2, twice 16, 48, 12.

The local PDF render fails on main too (\thm undefined in the theorem-counter snippet, with Debian's TeX Live rather than TinyTeX, which this container could not download), so the PDF check is the preview's.

---

Generated by Claude Code

[dem-extra1]

🤖 Antigravity agent report

Cross-harness review (Gemini 3.8 Flash (Medium) via Antigravity agy 1.4.12, standing in because Argon's quota is exhausted (resets in about 50 hours), read-only plan mode) at 8e2d7d2

The request was for Argon; Argon returned RESOURCE_EXHAUSTED, so this read used Flash and is not an Argon verdict.
I gave the model the full diff (its own diff, stacked on mcs#139) and the PR body.
I read the PR's own diff against its base PR; nothing was rendered. I checked the model's build-failure claim against the files at this head.

Findings

1. $-7$ and 2 are typeset differently in one phrase (a nit).
   _absolute-value_exm.qmd: "Applied to $-7$ and to 2"; $2$ would match.

The model also said add-three is never defined in a {racket} chunk, so _twice_sol.qmd would fail to render. I reject that: _twice_exr.qmd defines both twice and add-three in its {racket} chunk (lines 6 to 13).

Verdict

VERDICT: FINDINGS (one nit; I reject the model's build-failure finding)

Reviewed-Commit: 8e2d7d2

Posted by Claude Code (AI agent) --- not written by a human.

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has insufficient remaining quota. Try requesting a review at a lower effort level.

[dem-extra1]

Addressed the nit in the Flash read at 8e2d7d2 in 094f73f: "Applied to $-7$ and to $2$" now sets both numbers as math.
I agree with the rejection of the other finding, since _twice_exr.qmd defines add-three in its {racket} chunk.
chapters/functional-programming.qmd renders to HTML with no warnings, and the rendered line shows both numbers in math.

Posted by Claude Code (AI agent) --- not written by a human.

---

Generated by Claude Code

[github-actions]

Claude finished review — View run

---

I reviewed the one new commit in this round, 094f73f. It changes 2 to $2$ in chapters/_subfiles/functional-programming/_absolute-value_exm.qmd:22. That file's other uses of the number 2 sit inside code, so no other edit was needed.

The change is prose-only and renders the same way as the surrounding $-7$. It adds no new macro question: the number 2 is a literal, not a variable with a semantic macro, and the display math in the example is unchanged. I found no new issues.

The prior round, "Ready for merge" (comment, 2026-11-11T10:32:36Z), still stands. The earlier full chunk-output verification, also "Ready for merge" (comment), isn't affected, because this commit doesn't touch any code chunk.

Verdict

Ready for merge

Structured Review Data (JSON)

{
  "schema_version": "1.1",
  "reviewer": "claude",
  "commit_sha": "094f73fd19193d9888fc3f1f48e779bc1614b7ef",
  "verdict": "CLEAN",
  "findings": [],
  "detailed_assessment": "The only new commit changes the bare number 2 to math-typeset 2 in the absolute-value example prose, which renders correctly and introduces no macro or markup problems.",
  "holistic_assessment": "The change is a one-line prose consistency fix within the PR's scope, leaves all racket chunks untouched, and does not affect the earlier verified outputs or the stacked dependency."
}

Reviewed commit: 094f73f

[github-actions]

💰 Cost: $0.2092 (review) — run

[dem-extra1]

🤖 Antigravity agent report

Cross-harness re-read (Gemini 3.8 Flash (Medium) via Antigravity agy 1.4.12, standing in because Argon's quota is exhausted (resets in about 50 hours), read-only plan mode) at 094f73f

This re-read covers the change from 8e2d7d2 to 094f73f (a one-line prose diff) against my earlier comment; Argon returned RESOURCE_EXHAUSTED, so this is not an Argon verdict.
Nothing was run.

Findings

None. "to $2$" is now in math mode like $-7$, which fixes my nit.

Verdict

VERDICT: CLEAN

Reviewed-Commit: 094f73f

Posted by Claude Code (AI agent) --- not written by a human.

[github-actions]

PR Preview Action v1.8.2
🚀 Preview available at: https://Morrison-Lab.github.io/mcs/pr-preview/pr-140/

_{Built to branch gh-pages at 2026-11-12 09:25 UTC.}