The definitive JavaScript type testing library
To be or not to be? This is the library!
As a node.js module
$ npm install is
As a component
$ component install enricomarino/is
is.a (value, type) or is.type (value, type)is.defined (value)is.empty (value)is.equal (value, other)is.hosted (value, host)is.instance (value, constructor)is.instanceof (value, constructor) - deprecated, because in ES3 browsers, "instanceof" is a reserved wordis.nil (value)is.null (value) - deprecated, because in ES3 browsers, "null" is a reserved wordis.undef (value)is.undefined (value) - deprecated, because in ES3 browsers, "undefined" is a reserved wordis.args (value)is.arguments (value) - deprecated, because "arguments" is a reserved wordis.args.empty (value)is.array (value)is.array.empty (value)is.arraylike (value)is.bool (value)is.boolean (value) - deprecated, because in ES3 browsers, "boolean" is a reserved wordis.false (value) - deprecated, because in ES3 browsers, "false" is a reserved wordis.true (value) - deprecated, because in ES3 browsers, "true" is a reserved wordis.date (value)is.element (value)is.error (value)is.fn (value)is.function (value) - deprecated, because in ES3 browsers, "function" is a reserved wordis.number (value)is.infinite (value)is.decimal (value)is.divisibleBy (value, n)is.integer (value)is.int (value) - deprecated, because in ES3 browsers, "int" is a reserved wordis.maximum (value, others)is.minimum (value, others)is.nan (value)is.even (value)is.odd (value)is.ge (value, other)is.gt (value, other)is.le (value, other)is.lt (value, other)is.within (value, start, finish)is.object (value)is.regexp (value)is.string (value)is.base64 (value)is.hex (value)is.symbol (value)is.bigint (value)Lodash is a modern JavaScript utility library that provides a wide range of functions for common programming tasks, including type checking and validation. It offers similar functionality to 'is' but with a broader scope and additional utilities for working with arrays, objects, and more.
Validator is a library for string validation and sanitization. It provides a comprehensive set of functions for validating and sanitizing strings, including checks for email addresses, URLs, and credit card numbers. It is more focused on string validation compared to 'is'.
Type-detect is a library for type detection in JavaScript. It provides functions to determine the type of a variable, similar to the type checking features of 'is'. It is a lightweight alternative focused specifically on type detection.
FAQs
the definitive JavaScript type testing library
The npm package is receives a total of 1,144,790 weekly downloads. As such, is popularity was classified as popular.
We found that is demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 1 open source maintainer collaborating on the project.
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