TypeScript Library

A library of native TypeScript functions and data structures with no external dependencies.

Install

npm install github:baloian/lib-ts

Usage

import { pctDiff } from '@baloian/lib-ts';

const diff: number = pctDiff(100, 50);
console.log(diff);

Functions

// Function makes the program sleep for a given number of milliseconds.
sleep(ms: number): Promise<any>

// Rounding number to a decimal place
round(value: number, decimals: number = 2): number

// Get time difference in human readable form.
timeDiff(start: number, end: number, rounded: boolean = false): string

// Calculates percentage change of two values (current and previous).
pctDiff(current: number, previous: number): number

// Calculates what percentage VALUE is of TOTAL.
pctOf(value: number, total: number): number

// Returns the sum of the property value in the array of objects.
sumOfPropVal(list: unknown[], prop: string): number

/*
* Fisher-Yates shuffle algorithm, Durstenfeld's variant as described in
* https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
*
* This function shuffles the given array in-place.
*/
shuffle<T>(array: T[]): void

/*
* Returns random element (array[i]) of array such that 0 <= i < array.length
* The random implementation avoids modulo bias.
*/
getRandomElemOfArray<T>(data: T[]): T | undefined

/*
 * Convert a number to a USD dollar value.
 * For example, formatToUSD(123459.87) -> $123,458.87
 */
formatToUSD(amount: number): string

// Copy object
deepCopy<T>(obj: T): T

// Convert a number (representing a month) to a month name.
function numberToMonth(monthNumber: number): string | null

Data Structures

Queue

push(item: T): void;
pop(): void;
front(): T | undefined;
isEmpty(): boolean;
size(): number;
clear(): void;
updateFront(data: T): void;
getList(): T[];

Example

import { Queue, QueueType } from '@baloian/lib';

const q = new Queue<number>();
q.push(5);
console.log(q.front());

Contributions

Contributions are welcome and can be made by submitting GitHub pull requests to this repository. In general, the source code follows Airbnb JavaScript Style Guide and the rules specified in .eslintrc.json file.

License

This source code is available to everyone under the standard MIT LICENSE.