useful-utils.md

Some helper functions that can come in handy day to day.

utils.ts

export const asyncForEach = async <T>(arr: T[], cb: (item: T, index: number) => Promise<void> | void) => {
	for (let index = 0; index < arr.length; index++) await cb(arr[index], index);
};

export const makeArray = <T>(val: T | T[]) => (Array.isArray(val) ? val : [val]);

export const callIfFunction = <T, A>(item: T | ((...args: A[]) => T), val: A[]): T => {
	// @ts-ignore
	if (typeof item === 'function') return item(...val);

	return item;
};

export const removeArrayDuplicates = <T>(arr: T[]): T[] => {
	return [...new Set(arr)];
};

export function numDigits(n: number) {
	return (Math.log10((n ^ (n >> 31)) - (n >> 31)) | 0) + 1;
}

export const repeat = (num: number, cb: (index: number) => void) => {
	for (let index = 0; index < num; index++) cb(index);
};

export const multiplyString = (str: string, times: number) => {
	let result = ``;
	repeat(times, () => (result += str));
	return result;
};

export const isOk = (v: any) => {
	return v !== undefined && v !== null;
};

export const lastItem = <T>(arr: T[]): T => {
	return arr[arr.length - 1];
};

export const flattenArray = <T>(arr: T[][]): T[] => {
	const flattened: T[] = [];

	arr.forEach(i => flattened.push(...i));

	return flattened;
};

export function lazyJSONParse(json: string): any {
	try {
		return JSON.parse(json)
	} catch (e) {
		return {}
	}
}

export function delay(time: number) {
	return new Promise<void>(resolve => {
		setTimeout(() => resolve(), time)
	})
}