@olan88/utilities

A collection of typed utility functions for TypeScript projects.

Installation

npm install @olan88/utilities

String

import { capitalize, toCamelCase, truncate, slugify, toSnakeCase, toKebabCase } from "@olan88/utilities"

capitalize(str, numberOfLetters?)

Capitalizes the first numberOfLetters characters (default 1).

capitalize("hello")       // "Hello"
capitalize("hello", 2)    // "HEllo"

toCamelCase(str, capitalize?)

Converts a string to camelCase. Pass true for PascalCase. Handles hyphens, underscores, and spaces.

toCamelCase("hello-world")        // "helloWorld"
toCamelCase("hello_world")        // "helloWorld"
toCamelCase("hello-world", true)  // "HelloWorld"

toSnakeCase(str, uppercase?)

Converts a string to snake_case. Pass true for UPPER_SNAKE_CASE.

toSnakeCase("helloWorld")          // "hello_world"
toSnakeCase("helloWorld", true)    // "HELLO_WORLD"

toKebabCase(str)

Converts a string to kebab-case.

toKebabCase("helloWorld")   // "hello-world"
toKebabCase("hello_world")  // "hello-world"

truncate(str, maxLength, suffix?)

Truncates a string to maxLength characters, appending a suffix (default "…").

truncate("Hello, world!", 8)         // "Hello, …"
truncate("Hello, world!", 8, "...")  // "Hello..."

slugify(str)

Converts a string to a URL-friendly slug.

slugify("Hello World!")  // "hello-world"
slugify("Foo  Bar_Baz")  // "foo-bar-baz"

Number

import { clamp, randomInt } from "@olan88/utilities"

clamp(value, min, max)

Clamps a number between min and max.

clamp(5, 1, 10)   // 5
clamp(-5, 1, 10)  // 1
clamp(15, 1, 10)  // 10

randomInt(min, max)

Returns a random integer between min and max (both inclusive).

randomInt(1, 6)  // e.g. 4

Array

import { chunk, unique, groupBy } from "@olan88/utilities"

chunk(arr, size)

Splits an array into chunks of a given size.

chunk([1, 2, 3, 4, 5], 2)  // [[1, 2], [3, 4], [5]]

unique(arr)

Returns a new array with duplicate values removed.

unique([1, 1, 2, 3, 2])  // [1, 2, 3]

groupBy(arr, key)

Groups an array of objects by the value of a given key.

groupBy([{ type: "a" }, { type: "b" }, { type: "a" }], "type")
// { a: [{ type: "a" }, { type: "a" }], b: [{ type: "b" }] }

Object

import { pick, omit, deepClone } from "@olan88/utilities"

pick(obj, keys)

Returns a new object with only the specified keys.

pick({ a: 1, b: 2, c: 3 }, ["a", "c"])  // { a: 1, c: 3 }

omit(obj, keys)

Returns a new object with the specified keys removed.

omit({ a: 1, b: 2, c: 3 }, ["b"])  // { a: 1, c: 3 }

deepClone(obj)

Creates a deep clone of an object.

const clone = deepClone({ a: { b: 1 } })
clone.a.b = 99  // original is unaffected

Timer

import { wait, exponentialWait } from "@olan88/utilities"

wait(ms)

Waits for the specified duration.

await wait(1000)  // waits 1 second

exponentialWait(attempt, delay?, backoff?)

Waits for an exponentially increasing duration. Useful for retry logic.

await exponentialWait(0)  // 100ms
await exponentialWait(1)  // 200ms
await exponentialWait(2)  // 400ms