lv-ts-utils

Lightweight TypeScript utility kit with small, focused helpers for type guards, strings, arrays, and timing helpers. Published as ESM with bundled type definitions.

Installation

npm install lv-ts-utils
# or
yarn add lv-ts-utils
# or
pnpm add lv-ts-utils

Quick start

import { isString, debounce, capitalize } from "lv-ts-utils";

const logTyped = debounce((value: unknown) => {
	if (isString(value)) {
		console.log(capitalize(value));
	}
}, 300);

logTyped("hello world"); // → "Hello World"

API

Types

• AnyFunction: alias for (...args: unknown[]) => unknown, used by timing helpers.

Check

• isEmpty(value: unknown): boolean — returns true for non-objects and for objects with no enumerable entries.
• isNullOrUndefined(value): value is null | undefined — narrow to nullable values.
• isObject(value): value is object — plain object guard (excludes null, arrays, Date, RegExp).
• isString(value): value is string — string guard.

Strings

• capitalize(string): string — capitalizes the first letter of each space-separated word; if input is not a string, returns it unchanged.
• includes(string, substring): boolean — safe wrapper around String.prototype.includes; returns false if either argument is not a string.

Arrays

• arraylable(value): T[] — ensures an array; returns [] when input is null or not an array.
• map(array, fn): U[] — thin wrapper over Array.prototype.map for consistent import style.

Timing

• debounce(fn, delay = 200) — returns a debounced function that runs after inactivity for the given delay (default 200 ms).
• throttle(fn, delay = 500) — returns a throttled function that runs at most once per delay window (default 500 ms).

Test helpers

• hello() — logs Hello, world!.

Project scripts

• npm run build — type-check with tsc and build with vite.
• npm run lint — lint with Biome.
• npm run format — format with Biome.
• npm run check:types — Biome check plus tsc --noEmit.
• npm test — run Vitest with coverage.
• npm run test:mutation — run Stryker mutation tests.

Output

• Entry point: dist/ts-utils.js.
• Types: dist/types/index.d.ts.