mirror of
https://github.com/vercel-labs/scriptc.git
synced 2026-10-21 05:50:55 +08:00
Chris Tate
c48a21b9ef
- Object.create(null) is a real null-prototype dictionary: inspect, toString, and deepStrictEqual answer Node's forms; the dynamic tier routes to the engine's own Object.create for live delegation - Object prototypes fence by name in static builds — an own-copy stance is observably wrong under Node's empty-own-set answers and live proto mutations - entries() and keys() walk any static array live in for-of heads and iterator-helper chains - Object.assign(target, ...sources) packs spreads with JS's evaluation order before any copy, with V8's position-dependent error texts # Conflicts: # packages/compiler/test/ts7/baselines/order-parity.json # packages/runtime/src/scr_json.c
33 lines
1.5 KiB
TypeScript
33 lines
1.5 KiB
TypeScript
// arr.entries() as an iterator-helper chain SOURCE: the [index, element]
|
|
// pair seeds the fused per-element walk (the values() machinery with the
|
|
// pair built per pass), flowing through map/filter/flatMap/take/drop
|
|
// into every consuming terminal — the lazy pull order, live length
|
|
// re-reads, and take's close-before-delivery all carry over unchanged.
|
|
// Stage callbacks destructure the pair or take it whole; counters count
|
|
// each stage's own input stream. Node is the oracle byte-for-byte.
|
|
const words: string[] = ["alpha", "beta", "gamma", "delta"];
|
|
|
|
const tagged = words.entries().map(([i, w]) => `${i}:${w}`).toArray();
|
|
console.log(tagged.join(" "));
|
|
|
|
const odds = words.entries().filter(([i]) => i % 2 === 1).map(([, w]) => w).toArray();
|
|
console.log(odds.join(","));
|
|
|
|
words.entries().take(2).forEach(([i, w]) => console.log(i, w));
|
|
words.entries().drop(3).forEach(([i, w]) => console.log(i, w));
|
|
|
|
const total = [3, 4, 5].entries().reduce((acc, [i, n]) => acc + i * n, 0);
|
|
console.log(total);
|
|
|
|
const found = words.entries().find(([, w]) => w.startsWith("g"));
|
|
console.log(found === undefined ? "none" : `${found[0]} ${found[1]}`);
|
|
console.log(words.entries().some(([i]) => i > 2), words.entries().every(([i]) => i < 4));
|
|
|
|
// flatMap over pairs, and a whole-pair callback with a stage counter.
|
|
const flat = ["a", "b"].entries().flatMap(([i, s]) => [String(i), s]).toArray();
|
|
console.log(flat.join("|"));
|
|
const counted = words.entries().map((pair, n) => `${n}/${pair[0]}${pair[1]}`).take(3).toArray();
|
|
console.log(counted.join(" "));
|
|
|
|
console.log("done");
|