mirror of
https://github.com/vercel-labs/scriptc.git
synced 2026-10-23 06:10:02 +08:00
Chris Tate
057ac2cea2
- 2530-2535 and 2541 lock in the destructuring forms the static tier already compiled but the corpus never pinned: object/array/tuple declarations (renames, defaults, holes, nesting, fresh rest tails), the options-object parameter pattern (element and whole-pattern defaults, tuple/rest parameter patterns), for-of heads (containers, defaults, rest, existing bindings), object rest freshness and key order, assignment basics (swaps, chains, expression value), and evaluation order (RHS once, elements left to right, lazy defaults that see earlier bindings). - All byte-identical against Node under both backends, and each reports 100% static coverage.
52 lines
1.7 KiB
TypeScript
52 lines
1.7 KiB
TypeScript
// Destructuring in function/method parameters — the options-object
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// pattern: element defaults, whole-pattern defaults, tuple and array
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// patterns, arrows, methods, and rest-pattern parameters.
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interface Opts {
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port?: number;
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host?: string;
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secure?: boolean;
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}
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function serve({ port = 80, host = "localhost", secure = false }: Opts = {}): string {
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return `${secure ? "https" : "http"}://${host}:${port}`;
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}
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console.log(serve());
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console.log(serve({ port: 8443, secure: true }));
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console.log(serve({ host: "example.test" }));
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// A default reading an earlier binding of the same pattern.
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function span({ from = 0, to = from + 10 }: { from?: number; to?: number }): string {
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return `${from}..${to}`;
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}
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console.log(span({}));
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console.log(span({ from: 5 }));
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console.log(span({ from: 2, to: 4 }));
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// Tuple parameter patterns (the .map(([k, v]) => ...) shape).
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const entries: [string, number][] = [["a", 1], ["b", 2]];
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console.log(entries.map(([k, v]) => `${k}=${v}`).join("&"));
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// Array parameter patterns with rest.
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function tailLen([, ...rest]: number[]): number {
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return rest.length;
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}
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console.log(tailLen([1, 2, 3, 4]));
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// Nested parameter patterns.
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function describe({ id, meta: { tag } }: { id: number; meta: { tag: string } }): string {
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return `${id}:${tag}`;
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}
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console.log(describe({ id: 7, meta: { tag: "x" } }));
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// Methods and constructors take patterns too.
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class Server {
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private prefix: string;
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constructor({ prefix = ">" }: { prefix?: string } = {}) {
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this.prefix = prefix;
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}
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log({ level, msg }: { level: string; msg: string }): void {
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console.log(`${this.prefix}[${level}] ${msg}`);
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}
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}
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new Server().log({ level: "info", msg: "up" });
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new Server({ prefix: "$" }).log({ level: "warn", msg: "slow" });
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