Lucas WintherandClaude Fable 5.2
edd57f0148
Audit pass: - Frame rule counts frames since the last move, so every step lasts exactly movesEvery(score) frames, also right after a speed-up - clampTime + MAX_GAP_MS: a hidden tab no longer replays the whole gap - Pong Restart keeps held keys - Fact corrections (mulberry32 output coverage, Haskell IO, uniform) - New fixture cases from a mutation analysis Extensions (all three tracks, shared fixtures, course text): - Turn queue (Exercise 10.6), persisted high score (10.7), replay viewer (10.8), play() end-to-end helper (9.5) - Optional State (4.7) and optional Module 7b, stack-safe IO - Module 12, property-based testing with generators, shrinking, invariants and a model-based oracle - Module 13, Conway's Life with a Click event - JS type checking via jsconfig, JSDoc and types.d.ts - Maintainer tools: scripts/mutate.mjs, scripts/typecheck-js.sh, Playwright end-to-end suite (e2e/, scripts/e2e.sh) Docs: docs/contract.md is the canonical contract; specs and build log under docs/superpowers. Verified: JS 728, Scala 689, F# 691 unit tests; stubs and progression M01-M13 and M07b; 176 end-to-end tests on Chromium and WebKit. Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
39 lines
1.6 KiB
JavaScript
39 lines
1.6 KiB
JavaScript
// m04 random: a tiny "state monad" for randomness. A Random<A> is a function seed -> [A, nextSeed],
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// so every draw is a pure function and the seed is passed along explicitly instead of hidden.
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/** @import { Random } from './types' */
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/** mulberry32: a small, fast generator. `imul` is 32-bit integer multiplication (plain `*` would lose bits).
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* @type {Random<number>} */
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export const nextUint32 = (seed) => {
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const s = (seed + 0x6D2B79F5) >>> 0 // `>>> 0` keeps numbers unsigned 32-bit
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const t1 = Math.imul(s ^ (s >>> 15), s | 1)
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const t2 = t1 ^ (t1 + Math.imul(t1 ^ (t1 >>> 7), t1 | 61))
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return [(t2 ^ (t2 >>> 14)) >>> 0, s]
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}
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/** A Random that always gives `a` and leaves the seed untouched.
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* @type {<A>(a: A) => Random<A>} */
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export const pure = (a) => (seed) => [a, seed]
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/** Transform the value a Random produces; the seed threading is unchanged.
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* @type {<A, B>(r: Random<A>, f: (a: A) => B) => Random<B>} */
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export const map = (r, f) => (seed) => {
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const [a, next] = r(seed)
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return [f(a), next]
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}
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/** Run `r`, let `f` pick the next Random from its value, and run that with the seed `r` left behind.
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* @type {<A, B>(r: Random<A>, f: (a: A) => Random<B>) => Random<B>} */
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export const flatMap = (r, f) => (seed) => {
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const [a, next] = r(seed)
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return f(a)(next)
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}
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/** A Random giving a number in `[0, n)`.
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* @type {(n: number) => Random<number>} */
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export const intBelow = (n) => map(nextUint32, (v) => v % n)
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/** Run a Random from a seed: `[value, nextSeed]`.
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* @type {<A>(r: Random<A>, seed: number) => [A, number]} */
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export const run = (r, seed) => r(seed)
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