JSPM

Check if an environment is big endian.

Test if a double-precision floating-point numeric value is infinite.

Test if a value is a regular expression string.

maximally minimal type-testing library

Check if a string is HTML

ESLint shareable config for XO

ESLint shareable config for the Google style

Check if a URL is relative

Test if a value is a string.

Test if a value is an object.

Test if a value is a number.

Try to downgrade the permissions of a process with root privileges and block access if it fails

Test if a value is a Float32Array.

Test if a value is a boolean.

Test if a value is a function.

Test if a value is a Float64Array.

A simple and composable way to validate data in JavaScript (and TypeScript).

Test if a value is a Uint32Array.

Get a property from an object using dot (object path) notation.

Check for outdated, incorrect, and unused dependencies.

JavaScript/TypeScript linter (ESLint wrapper) with great defaults

Determine the specification defined classification of an object.

check if an AST node is a function of some sort

Test if a value is a Buffer object.

Test if a value is a plain object.

Test whether a path exists on the filesystem.

Tiny wrapper around ansi-colors to add colored symbols and a timestamp.

Test if a value is a regular expression.

Check TypeScript type definitions

Determine a value's type.

Test if a double-precision floating-point numeric value is NaN.

Check if a Buffer/Uint8Array is a TAR file

Test if a value is a Uint8Array.

Test if a value is a Uint16Array.

Is this a bluebird promise I see before me?

Check if an environment is little endian.

Detect potential issues with users system that could prevent Yeoman from working correctly

Check if browser is Firefox

Check if a value is a `Blob`

Check if a process is running

Check if browser is Internet Explorer

Check whether a binary exists in the PATH environment variable

Promisified version of node-which

ESLint shareable config for TypeScript to be used with eslint-config-xo

Utilities to get and check variable types (isString, isPlainObject, isRegExp, etc)

Verify if something is a Promise

Check if Electron is running in development

Detect the audio type of a Buffer/Uint8Array

Checks if the given value is null or undefined

Is given string a language code (as per IANA)

check if the current node version has async_hooks.

Checks if a given object is iterable

Determine if an array or object is equivalent with another, *not* recursively

Checks TypeScript types match expected values

Reshape into a better npm audit for the community and encourage more people to include security audit into their process.

Checks if the given value is a native function.

Check if a string is a valid JavaScript identifier

check if an AST node is a MemberExpression, in general or a specific one

Check whether a package or organization name is available on npm

Check if a string is an IP address

Returns true if the given is falsey (according to JavaScript) or matches a 'falsey' keyword.

A gulp plugin for processing files with ESLint

3x as fast as `is-whitespace` and `whitespace-regex` thanks to `is-string-blank`. This package is a simple function that accepts an argument and returns `true` if it is a string AND it is not blank. Supports Node and Browser environments.

Keep watch of your bundle size

Looks up the first non-whitespace character to the left/right of a given index

JavaScript Standard Style React/JSX support - ESLint Shareable Config

Check if a Buffer/Uint8Array is a ZIP file

Check if a directory is empty.

A TypeScript ESLint config that loves you

A JSON fixer

Ember CLI addon for detecting missing npm and bower dependencies before executing ember commands

Utils to deal with TCP ports and hostnames. Safe for everyday use.

Parse dotenv files for Boolean, Array, and Number variable types, built for CrocodileJS

Detect the image type of an ArrayBuffer/Uint8Array

A proxy to `path`, replacing `\` with `/` for all results

checks the all of the hyperlinks in a markdown text to determine if they are alive or dead

checks whether a hyperlink is alive (200 OK) or dead

Check if a value is a function

Check if a Node.js Buffer or Uint8Array is UTF-8

JavaScript Semistandard Style - ESLint Shareable Config

Validates password according to flexible and intuitive specifications

ESLint shareable config for React to be used with eslint-config-xo

ESLint shareable config for XO with 2-space indent

Check if a Buffer/Uint8Array is a BZIP2 file

Test if a finite numeric value is an odd number.

is-iojs determines if runtime is io.js.

Check if a string is a valid filename

Checks for URLs during typing and pasting and automatically converts them to links.

Keep your library size in check

allows easy type enforcement for all JS types objects and classes. it is also extensible and provides simple to use type checks for your own custom classes and types

Returns true if an object has an own, nested property using dot notation paths ('a.b.c').

Check the validity of the format of an EU VAT number

Check if an object is an array or a typed array

Context menu for your Electron app

A collection of functions for working with different casings.

Test if a finite double-precision floating-point number is an integer.

Aids humans and automation in managing npm audit results

Validate hostname based on RFC-1123

Check whether a binary version satisfies a semver range

Test if a double-precision floating-point numeric value is positive zero.

Check if the machine is running Windows or not.

Test if a value is NaN.

Hunspell compatible spell checker

Returns `true` if a value exists in the given string, array or object.

TypeScript Standard Style based on StandardJS

Check if the package is being installed by another package

Test if a value is a number having an integer value.

Check if the process is running as administrator on Windows

Test if a value is a number having a nonnegative integer value.

Test if a value is an Int32Array.

Detect the appearance of an element in the browser DOM

TypeScript / JavaScript library for detect WebAssembly features in node.js & browser

Test if an object's own property is enumerable.

Check if a value is undefined or not.

Test if a value is a Uint8ClampedArray.

Test if a value is an Int16Array.

Test if a finite numeric value is an even number.

Assert a given object is a valid glob option

$(document).ready() for the 21st century

Async npm module for Node JS that reads the first line of a file

Markdown TaskList components

Checks that given package is installed globally or locally.

Returns true if the current node version matches the given semver expression

Check if the user is running the latest version of the app

All the goodness of `feross/standard` with semicolons sprinkled on top.

Check if the process is running with elevated privileges

A pure css library to beautify checkbox and radio buttons.

Test if a value is an Int8Array.

A command line utility to read version from package.json and attach it into your module as a property

Test if a value is a collection.

Test if a double-precision floating-point numeric value is negative zero.

code > prettier > stylelint > formatted code

Test if a value is an arguments object.

Validate glob options

ESlint plugin to define custom module dependency rules.

Create an error from the result of validate-glob-opts

Check if a file path is an image

A tool to enable the checking, inserting and removal of licenses

Fully customizable animated bouncy checkbox for React Native

Get or set a deep value using a keypath string. Supports bracket and dot notation

Checks if an input string is a capitalized or not.

Standard assertion utilities.

Skema provides a handy & composable way to validate / transform / purify the input data.

Test if a value is an Error object.

allows easy type enforcement for all JS types objects and classes. it is also extensible and provides simple to use type checks for your own custom classes and types

Test whether a value has in its prototype chain a specified constructor as a prototype property.

Run your TypeScript type tests using Jest

Base58Check encoding

check if an AST node is a call to require()

A gulp plugin to lint code with ESLint 8 and 9.

Compile TypeScript interfaces into a description that allows runtime validation

Test if a value is an ArrayBuffer.

Test if a value is a number having a positive integer value.

Get or check the current macOS version

Minimal JavaScript type checking library

Test if a value is a complex number-like object.

Set of various predicates for type checking, assertions, filtering etc

Checks if the given value is an array or array-like object.

Easily expose your http server's health.

Test if a value is an array-like object.

Check if something is a positive number

Determines whether a string ends with the characters of another string.

Test if a value is a number having a positive value.

Test if a value is array-like.

check if an AST node is a call to require()

Shallow equal check object.

Assertions and Validations for TypeScript

Test if a value is a Complex64Array.

Run elm-review from Node.js

Check if something is a Node.js stream. This is a fork of sindresorhus/is-stream, but with CommonJS support.

Check if a String/Buffer is TTF

Lint CSS for email support against caniemail database.

Type check values: `is.string('🦄') //=> true`

Upcast is a low-level JavaScript type checking and casting library

Check if a number is in a given range

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Noir ESLint shareable config

Check that all files match prettier code style.

Check types

Test if a finite double-precision floating-point number is a nonnegative integer.

Test if a value is a typed array.

Test if a value is a complex typed array.

ESLint sharable config for strict linting

Check whether a file can be executed

Check if a file path is a video file

Test if a value is a Complex128Array.

Check if a file is a directory

Check if an Array is sorted

Test if an array-like object supports the accessor (get/set) protocol.

Return a function which tests if every element in an array-like object passes a test condition.

A light-weight jQuery "dirty forms" Plugin - it monitors HTML forms and alerts users to unsaved changes if they attempt to close the browser or navigate away from the page. (Are you sure?)

Test if a value is an array-like object of numbers.

Utilities for formatting and linting a Dockerfile.

Test whether a module is available as a dependency

Check if a JavaScript environment has a DOM

Check if a String/Buffer/ArrayBuffer is OTF

Type checking for .eslintrc.json

Utility to check if internet is connected or not

Returns true if an array has duplicate elements or a string has duplicate characters.

Tiny, streaming, seedable CRC32 library, compatible with the crypto.Hash API

Check if NPM package names conflict

Test if a value is typed-array-like.

Check the validity of the format of an EU VAT number

Returns true if a value is the global or window object.

Validates if a value is a JavaScript object.

Determine if a variable or expression is a React element or component

Library to check variable type and properties in object.

Build a navigation structure programatically

Checkbox component for react native, it works on iOS and Android.

If X, return Y, else throw Z.

Check if something is a negative number

Convert Ethereum address to a checksummed address

Check that given value is valid hex color, using `hex-color-regex` - the best regex for matching hex color values

Test if a finite double-precision floating-point number is a negative integer.

Build templates for initial values

Delete files and folders and any intermediate directories if they exist (sync and async).

Check if a string can be used as a JavaScript variable name

[![github actions][actions-image]][actions-url] [![coverage][codecov-image]][codecov-url] [![dependency status][deps-svg]][deps-url] [![dev dependency status][dev-deps-svg]][dev-deps-url] [![License][license-image]][license-url] [![Downloads][downloads-im

check if urls are dead or alive

Check if an email domain belongs to an educational instutition

Validates if a value is undefined.

Validate the name of a custom element

Check to see if a token is expired using only the token itself without a secret key or validation

Check if an environment is little endian.

A simple function for interrupting program flow if a condition isn’t met.

Test if an array-like value contains a search value.

Tiny module for checking if Promise is globally available

Run commands if on specified node version.

Test if a value is a probability.

Checks the integrity of an Endo bundle.

Check if an object is empty or not.

The hasNestedProperty method missing in Object. This module does not extend Object.

Check your Vue project for unused Components

Verifies email domains

🔌 CLI to check/generate .env files and maintain them synchronized

Robustly checks an array of URLs for liveness.

Check if a string or buffer ends with a given string

Create JSON Schema validator from TypeScript.

Keep your package.json version requirements satisfied

Check a character if it is a correctly supported emoji.

Check if a Buffer/Uint8Array is WOFF

Check if a Buffer/Uint8Array is a FLAC file.

Checks if the given value is a valid array-like index.

Test if a finite double-precision floating-point number is a positive integer.

Check if a buffer/Uint8Array is a woff2 file

Check if a Buffer/Uint8Array is EOT

Check if two numbers are equal within a given tolerance

Utility for linting a docker file against accepted good practices

Check if node_modules match package.json versions. npm / yarn install shortcut.

Test if a double-precision floating-point number is a probability.