tonkotsuboy

/**
 * Math.clamp()
 */
export const mathClamp = (x: number, lower: number, upper: number): number => {
  return Math.min(Math.max(x, lower), upper)
}

tonkotsuboy

import { validateDate } from "./validateDate";

describe("有効な日付のテスト", () => {
  it.each(["2021/01/01", "2021/12/31", "2021/02/01", "2000/02/29"])(
    "%sは正しい日付である",
    (date) => {
      expect(validateDate(date, "YYYY/MM/DD")).toBe(true);
    }
  );

tonkotsuboy

describe("describe 1", () => {
  beforeEach(() => {
    console.log("before each 1");
  });

  describe("describe 2", () => {
    beforeEach(() => {
      console.log("before each 2");
    });
    it("test1", () => {});

tonkotsuboy

const myArray = [
  { name: 'ギータ', age: 32 },
  { name: 'マッチ', age: 37 },
  { name: 'ケイゾー', age: 37 },
  { name: '高谷', age: 39 },
];

// myArrayから、ageが37の最後の要素を探し、名前を取得
const targetName = myArray.findLast(member => {
  return member.age === 37;

tonkotsuboy

// this sample can be run with: $ node myTest.mjs
console.log("こんにちは");
await new Promise(resolve => {
  setTimeout(() => {
    console.log("2秒経ちました");
    resolve();
  }, 2000);
});

tonkotsuboy

class MyClass {
  // public field
  foo = "public field: 寿司";
  // private field
  #bar = "private field: ラーメン";

  // public static field
  static qux = "public static field: うどん";
  // private static field
  static #corge = "private static field: 麻婆豆腐";

tonkotsuboy

const parseOgImage = (htmlString: string): string | null => {
  return htmlString.match(/property="og:image" content="(?<ogimage>.*)"/iu)
    ?.groups.ogimage ?? null;
};

tonkotsuboy

class Fukuoka {
  get #ramen() {
    return "ラーメン";
  }

  #sayHello() {
    console.log(`${this.#ramen}はえらい美味しかばい`);
  }

  constructor() {

tonkotsuboy

const regrex = /よく(?<food>.*)食う(?<animal>.*)だ/u;

const result1 = "隣の客はよく柿食う客だ".match(regrex);
console.log(result1.groups.food);
console.log(result1.groups.animal);

const result2 = "隣の客はよく牡蠣食う吉田拓郎だ".match(regrex);
console.log(result2.groups.food);
console.log(result2.groups.animal);

tonkotsuboy

// 配列の最初の要素、長さ、最終要素をワンライナーで取得する
// 参考: https://twitter.com/argyleink/status/1139415654132436993

// 対象の配列
const myArray = ["😸", "🐶", "🐟", "🦆", "🐳", "🦉"];

// firstに最初の要素、lに長さ, lastに最終要素
const { 0: first, length: l, [l-1]: last} = myArray;

// 確認のため出力。結果は{first: "😸", l: 6, last: "🦉"}