is

the definitive JavaScript type testing library

Usage no npm install needed!

<script type="module">
  import is from 'https://cdn.skypack.dev/is';
</script>

README

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The definitive JavaScript type testing library

To be or not to be? This is the library!

Installation

As a node.js module

$ npm install is

As a component

$ component install enricomarino/is

API

general

  • 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 word
  • is.nil (value)
  • is.null (value) - deprecated, because in ES3 browsers, "null" is a reserved word
  • is.undef (value)
  • is.undefined (value) - deprecated, because in ES3 browsers, "undefined" is a reserved word

arguments

  • is.args (value)
  • is.arguments (value) - deprecated, because "arguments" is a reserved word
  • is.args.empty (value)

array

  • is.array (value)
  • is.array.empty (value)
  • is.arraylike (value)

boolean

  • is.bool (value)
  • is.boolean (value) - deprecated, because in ES3 browsers, "boolean" is a reserved word
  • is.false (value) - deprecated, because in ES3 browsers, "false" is a reserved word
  • is.true (value) - deprecated, because in ES3 browsers, "true" is a reserved word

date

  • is.date (value)

element

  • is.element (value)

error

  • is.error (value)

function

  • is.fn (value)
  • is.function (value) - deprecated, because in ES3 browsers, "function" is a reserved word

number

  • is.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 word
  • is.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)

object

  • is.object (value)

regexp

  • is.regexp (value)

string

  • is.string (value)

encoded binary

  • is.base64 (value)
  • is.hex (value)

Symbols

  • is.symbol (value)

BigInts

  • is.bigint (value)

Contributors