v12.3.0

New Functions

Add isClass function → PR #239

The isClass function determines if a value was declared using ES6 class syntax, distinguishing modern class declarations from traditional constructor functions or other types.

• Only returns true for values created with the class keyword
• Old-style constructor functions will return false
• Built-in native class constructors (like Error) return false
• Works with type narrowing for TypeScript

import * as _ from 'radashi'

class MyClass {
  x = 1
}

function OldConstructor() {
  this.x = 1
}

// Examples
_.isClass(MyClass) // true
_.isClass(OldConstructor) // false
_.isClass('string') // false
_.isClass(Error) // false

Thanks to Marlon Passos and Alec Larson for their work on this feature!

🔗 Docs / Source / Tests

 

Add isNullish function → PR #277

The isNullish function is a type-checking utility that determines whether a given value is either null or undefined. It helps you avoid the typos that an x == null check is prone to, and it's shorter to write than x === undefined || x === null.

import * as _ from 'radashi'

// Basic usage examples
_.isNullish(null) // true
_.isNullish(undefined) // true
_.isNullish('') // false
_.isNullish([]) // false
_.isNullish(0) // false

Thanks to Wei Xiaopeng for their work on this feature!

🔗 Docs / Source / Tests

 

Add cartesianProduct function → PR #241

The cartesianProduct function generates all possible combinations of elements from multiple input arrays, creating a new array containing every unique permutation of elements from those arrays.

• Works with any number of input arrays
• Returns an array of arrays representing all combinations
• Preserves the order of input arrays in the resulting combinations
• Can handle arrays of different types

import * as _ from 'radashi'

const colors = ['red', 'blue']
const numbers = [1, 2, 3]
const booleans = [true, false]

// Generate all combinations of colors, numbers, and booleans
const combinations = _.cartesianProduct(colors, numbers, booleans)

Thanks to Yam Borodetsky, Marlon Passos, and Alec Larson for their work on this feature!

🔗 Docs / Source / Tests

 

Add isUndefined function → PR #305

The isUndefined function is a type guard that checks whether a given value is specifically undefined. It provides a simple and type-safe way to determine if a value has been left unassigned or is explicitly set to undefined.

• Strictly checks for undefined using the typeof operator
• Can be used for type narrowing in TypeScript

import * as _ from 'radashi'

// Basic usage examples
const result1 = _.isUndefined(undefined) // true
const result2 = _.isUndefined(null) // false
const result3 = _.isUndefined(42) // false

Thanks to RobinBobin for their work on this feature!

🔗 Docs / Source / Tests

 

Add timeout function → PR #250

The timeout function creates a promise that rejects after a specified delay, providing a way to set timeouts for asynchronous operations. It allows customizing the error message or type of error thrown when the timeout occurs.

• Can be used with a default TimeoutError or a custom error message/function
• Primarily useful with Promise.race to add timeout functionality to async tasks

import * as _ from 'radashi'

// Basic usage: reject after 1 second with default TimeoutError
const basicTimeout = _.timeout(1000)

// With custom message
const customMessageTimeout = _.timeout(1000, 'Operation took too long')

// With Promise.race to limit async task duration
const someAsyncTask = async () => {
  await _.sleep(5000) // Simulate a long-running task
  return 'Task completed'
}

// Will reject after 1 second if task doesn't complete
const racedTask = await Promise.race([
  someAsyncTask(),
  _.timeout(1000, 'Task exceeded time limit'),
])

Thanks to Marlon Passos and Alec Larson for their work on this feature!

🔗 Docs / Source / Tests

 

Add dedent function → PR #120

The dedent function removes indentation from a multi-line string, making it easy to format and clean up text templates while preserving the relative indentation of embedded content.

• Supports both explicit and auto-detected indentation
• Works with tagged template strings
• Automatically handles multi-line embedded strings
• Removes the first leading and first trailing empty line
• Preserves relative indentation of content

import * as _ from 'radashi'

// Remove auto-detected indentation
const message = _.dedent`
  Hello, world!
  This is a dedented message.
`
// => 'Hello, world!\nThis is a dedented message.'

// Remove specific indentation
const customMessage = _.dedent('\n    Hello\n    World!\n\n', '  ')
// => '  Hello\n  World!\n'

Thanks to Alec Larson for their work on this feature!

🔗 Docs / Source / Tests

 

New Features

Add signal option to retry → PR #262

The new feature introduces an optional signal parameter to both the retry function, allowing for manual interruption of async operations using AbortController.

• The signal option accepts an AbortController.signal
• When the signal is aborted, no more calls to the callback will be made
• Aborting will throw a DOMException with the message "This operation was aborted"
• Works consistently across Node.js and browser environments

import * as _ from 'radashi'

const abortController = new AbortController()
const signal = abortController.signal

const promise = _.retry(
  { times: 3, delay: 1000, signal },
  async () => await fetchSomeData(),
)

// To abort the operation:
abortController.abort()

Thanks to ts-saidbe.abdiganiev and Alec Larson for their work on this feature!

 

Add signal option to parallel → PR #262

The latest update adds an optional signal option to the parallel function, allowing you to interrupt parallel processing with an AbortController.

• The signal option works with an AbortController.signal
• When aborted, it will throw a DOMException with an "AbortError" name
• Interruption only stops future iterations, not in-progress async calls
• Signals are compatible with both browser and Node.js environments

import * as _ from 'radashi'

// Abort a parallel operation
const abortController = new AbortController()
const signal = abortController.signal

const pizzas = await _.parallel(
  { limit: 2, signal },
  ['pepperoni', 'cheese', 'mushroom'],
  async topping => {
    return await bakePizzaInWoodFiredOven(topping)
  },
)

// Abort the operation if needed
abortController.abort()

Thanks to ts-saidbe.abdiganiev and Alec Larson for their work on this feature!

 

Tolerate out-of-range parallel limit → PR #238

The parallel function now automatically clamps the concurrency limit between 1 and the input array's length, ensuring more predictable and safe parallel processing.

• Previously, passing a limit larger than the array length or less than 1 could cause unexpected behavior
• The limit is now automatically adjusted to be within the valid range

import * as _ from 'radashi'

// Limit will be adjusted to 3 (array length)
const results = await _.parallel(
  10,
  ['item1', 'item2', 'item3'],
  async item => {
    // Process each item
    return item.toUpperCase()
  },
)

Thanks to Marlon Passos and Alec Larson for their work on this feature!