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// Fetch Standard

// prototype pollution
Object.prototype.toJSON = () => ({ foo: "foo" });

const response = Response.json({ bar: "bar" });
console.log(await response.json());

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// HTML Standard

const { map, arr, obj } = structuredClone((() => {
  const [map, arr, obj] = [new Map(), [], {}];
  map.a = "a"; arr.b = "b"; obj.c = "c";
  return { map, arr, obj };
})());
console.log(`${map.a} / ${arr.b} / ${obj.c}`);

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import idl from "@webref/idl";

const serializables = [];
const transferables = [];

const all = await idl.parseAll();
for (const file of Object.values(all)) {
  for (const obj of file) {
    if (obj.type !== "interface") {
      continue;

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/**
 * @file Strict TypedArray Type Check inspired by Node.js util.types implementation
 * @see https://github.com/nodejs/node/blob/v16.x/lib/internal/util/types.js
 */

const TypedArrayPrototype = Object.getPrototypeOf(Uint8Array).prototype;
const getTypedArrayPrototypeSybolToStringTag = Object.getOwnPropertyDescriptor(TypedArrayPrototype, Symbol.toStringTag).get;

/**
 * @param {unknown} value

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// TypedArray constructor

// Array
const uint8_1 = new Uint8Array([1, 2, 3]);
console.log(uint8_1);
// => Uint8Array(3) [1, 2, 3]

// ArrayLike
const uint8_2 = new Uint8Array({ 0: 1, 1: 2, 2: 3, length: 3 });
console.log(uint8_2);

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let isSupportedAbortSignalOption = false;

try {
  const options = {
    get signal() {
      isSupportedAbortSignalOption = true;
      return;
    },
  };
  (window.addEventListener as any)("test", null, options);

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import { useEffect, useState } from "react";

/**
 * @example
 *   const matches = useMatchMedia("screen and (min-width: 560px)");
 *
 * @param raw
 */
export function useMatchMedia(raw: string): boolean {
  const [matches, setMatches] = useState(false);

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import { useEffect, useMemo, useState } from "react";

/**
 * 後続の Iterator Value と合わせた Iterator を返す
 * (1, 2, 3) -> ([1, 2], [2, 3], [3, undefined])
 *
 * @param iterable
 */
function* withNext<T>(iterable: Iterable<T>): IterableIterator<[T, T | undefined]> {
  let isStart = true;

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http2-casper: ON
compress: ON

header.setifempty: "X-XSS-Protection: 1; mode=block"
header.setifempty: "Expect-CT: max-age=2592000, enforce"
header.setifempty: "Expect-Staple: max-age=31536000; includeSubDomains; preload"

listen:
  port: 80

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const Original = self.EventTarget;

let availabilityOfEventTargetConstructor = true;
try {
  new Original();
} catch {
  availabilityOfEventTargetConstructor = false;
}

/** @type {{ new(): EventTarget, prototype: EventTarget }} */