typical

Isomorphic, functional type-checking for Javascript.

Example

import t from 'typical'
const allDefined = array.every(t.isDefined)

• typical
  • .isNumber(n) ⇒ boolean
  • .isFiniteNumber(n) ⇒ boolean
  • .isPlainObject(input) ⇒ boolean
  • .isArrayLike(input) ⇒ boolean
  • .isObject(input) ⇒ boolean
  • .isDefined(input) ⇒ boolean
  • .isUndefined(input) ⇒ boolean
  • .isNull(input) ⇒ boolean
  • .isDefinedValue(input) ⇒ boolean
  • .isClass(input) ⇒ boolean
  • .isPrimitive(input) ⇒ boolean
  • .isPromise(input) ⇒ boolean
  • .isIterable(input) ⇒ boolean
  • .isString(input) ⇒ boolean
  • .isFunction(input) ⇒ boolean
  • .isAsyncFunction(input) ⇒ boolean

t.isNumber(n) ⇒ boolean

Returns true if input is a number (including infinity). It is a more reasonable alternative to typeof n which returns number for NaN.

Kind: static method of typical
Returns: boolean - true if input is a number

Param	Type	Description
n	*	The input to test

Example

> t.isNumber(0)
true
> t.isNumber(1)
true
> t.isNumber(1.1)
true
> t.isNumber(0xff)
true
> t.isNumber(0644)
true
> t.isNumber(6.2e5)
true
> t.isNumber(NaN)
false
> t.isNumber(Infinity)
true

t.isFiniteNumber(n) ⇒ boolean

Returns true if input is a finite number. Identical to isNumber beside excluding infinity.

Kind: static method of typical

Param	Type	Description
n	*	The input to test

Example

> t.isFiniteNumber(0)
true
> t.isFiniteNumber(1)
true
> t.isFiniteNumber(1.1)
true
> t.isFiniteNumber(0xff)
true
> t.isFiniteNumber(0644)
true
> t.isFiniteNumber(6.2e5)
true
> t.isFiniteNumber(NaN)
false
> t.isFiniteNumber(Infinity)
false

t.isPlainObject(input) ⇒ boolean

A plain object is a simple object literal, it is not an instance of a class. Returns true if the input typeof is object and directly decends from Object.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

Example

> t.isPlainObject({ something: 'one' })
true
> t.isPlainObject(new Date())
false
> t.isPlainObject([ 0, 1 ])
false
> t.isPlainObject(/test/)
false
> t.isPlainObject(1)
false
> t.isPlainObject('one')
false
> t.isPlainObject(null)
false
> t.isPlainObject((function * () {})())
false
> t.isPlainObject(function * () {})
false

t.isArrayLike(input) ⇒ boolean

An array-like value has all the properties of an array yet is not an array instance. An example is the arguments object. Returns true`` if the input value is an object, not null`` and has a length property set with a numeric value.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

Example

function sum(x, y){
  console.log(t.isArrayLike(arguments))
  // prints `true`
}

t.isObject(input) ⇒ boolean

Returns true if the typeof input is 'object' but not null.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isDefined(input) ⇒ boolean

Returns true if the input value is defined.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isUndefined(input) ⇒ boolean

Returns true if the input value is undefined.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isNull(input) ⇒ boolean

Returns true if the input value is null.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isDefinedValue(input) ⇒ boolean

Returns true if the input value is not one of undefined, null, or NaN.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isClass(input) ⇒ boolean

Returns true if the input value is an ES2015 class.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isPrimitive(input) ⇒ boolean

Returns true if the input is a string, number, symbol, boolean, null or undefined value.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isPromise(input) ⇒ boolean

Returns true if the input is a Promise.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isIterable(input) ⇒ boolean

Returns true if the input is an iterable (Map, Set, Array, Generator etc.).

Kind: static method of typical

Param	Type	Description
input	*	The input to test

Example

> t.isIterable('string')
true
> t.isIterable(new Map())
true
> t.isIterable([])
true
> t.isIterable((function * () {})())
true
> t.isIterable(Promise.resolve())
false
> t.isIterable(Promise)
false
> t.isIterable(true)
false
> t.isIterable({})
false
> t.isIterable(0)
false
> t.isIterable(1.1)
false
> t.isIterable(NaN)
false
> t.isIterable(Infinity)
false
> t.isIterable(function () {})
false
> t.isIterable(Date)
false
> t.isIterable()
false
> t.isIterable({ then: function () {} })
false

t.isString(input) ⇒ boolean

Returns true if the input value is a string. The equivalent of typeof input === 'string' for use in funcitonal contexts.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isFunction(input) ⇒ boolean

Returns true if the input value is a function. The equivalent of typeof input === 'function' for use in funcitonal contexts.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

t.isAsyncFunction(input) ⇒ boolean

Returns true if the input value is an async function or method.

Kind: static method of typical

Param	Type	Description
input	*	The input to test

Example

> t.isAsyncFunction(function () {})
false
> t.isAsyncFunction(new Function())
false
> t.isAsyncFunction(() => {})
false
> t.isAsyncFunction(async function () {})
true
> const AsyncFunction = async function () {}.constructor
> t.isAsyncFunction(new AsyncFunction())
true
> t.isAsyncFunction(async () => {})
true
> class Command { async execute () {} }
> t.isAsyncFunction(new Command().execute)
true

Load anywhere

This library is compatible with Node.js, the Web and any style of module loader. It can be loaded anywhere, natively without transpilation.

Within a Node.js ECMAScript Module:

import t from 'typical'
import { isNumber } from 'typical'

CommonJS:

const t = require('typical')
const { isNumber } = require('typical')

Within a modern browser ECMAScript Module:

import t from './node_modules/typical/index.js'

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© 2014-25 Lloyd Brookes <opensource@75lb.com>.

Test suite by test-runner. Documented by jsdoc-to-markdown.