Quick Functions in TypeScript

quick_functions.ts

// WAIT
const wait = (ms: number): Promise<void> => new Promise((resolve) => setTimeout(resolve, ms));
//await wait(1000); // waiting 1 second



// IS WEEKDAY
const isWeekday = (d: Date): boolean => d.getDay() % 6 !== 0;
//isWeekday(new Date(2022, 2, 21)); // -> true
//isWeekday(new Date(2021, 2, 20)); // -> false



//REVERSE
const reverse = (s: string): string => s.split('').reverse().join('');
//reverse('elon musk'); // -> 'ksum nole'



// IS EVEN
const isEven = (n: number): boolean => n % 2 === 0;
//isEven(2); // -> true
//isEven(3); // -> false



// CAPITALIZE
const capitalize = (s: string): string => s.charAt(0).toUpperCase() + s.slice(1);
//capitalize('lorem ipsum'); // -> Lorem ipsum



// IS ARRAY EMPTY
const isArrayEmpty = (arr: unknown[]): boolean => Array.isArray(arr) && !arr.length;
// isArrayEmpty([]); // -> true
// isArrayEmpty([1, 2, 3]); // -> false



// IS OBJECT EMPTY
const isObjectEmpty = (obj: unknown): boolean => obj && Object.keys(obj).length === 0;
// isObjectEmpty({}); // -> true
//isObjectEmpty({ foo: 'bar' }); // -> false



// RANDOM INTEGER
const randomInteger = (min: number, max: number): number => Math.floor(Math.random() * (max - min + 1)) + min;
//randomInteger(1, 10); // -> 7



// RANDOM BOOLEAN
const randomBoolean = (): boolean => Math.random() >= 0.5;
// randomBoolean(); // -> true




// TOGGLE BOOLEAN
const toggleBoolean = (val: boolean): boolean => (val = !val);
//toggleBoolean(true); // -> false