Isomorphic, functional type-checking for Javascript
npm install typical





Example
``js`
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
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
`js
> 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
`
$3
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
`js
> 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
`
$3
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
`js
> 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
`
$3
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
`js
function sum(x, y){
console.log(t.isArrayLike(arguments))
// prints true
}
`
$3
Returns true if the typeof input is 'object' but not null.Kind: static method of typical
| Param | Type | Description |
| --- | --- | --- |
| input | \* | The input to test |
$3
Returns true if the input value is defined.Kind: static method of typical
| Param | Type | Description |
| --- | --- | --- |
| input | \* | The input to test |
$3
Returns true if the input value is undefined.Kind: static method of typical
| Param | Type | Description |
| --- | --- | --- |
| input | \* | The input to test |
$3
Returns true if the input value is null.Kind: static method of typical
| Param | Type | Description |
| --- | --- | --- |
| input | \* | The input to test |
$3
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 |
$3
Returns true if the input value is an ES2015 class.Kind: static method of typical
| Param | Type | Description |
| --- | --- | --- |
| input | \* | The input to test |
$3
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 |
$3
Returns true if the input is a Promise.Kind: static method of typical
| Param | Type | Description |
| --- | --- | --- |
| input | \* | The input to test |
$3
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
`js
> 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
`
$3
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 |
$3
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 |
$3
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
`js
> 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:
`js
import t from 'typical'
import { isNumber } from 'typical'
`CommonJS:
`js
const t = require('typical')
const { isNumber } = require('typical')
`Within a modern browser ECMAScript Module:
`js
import t from './node_modules/typical/index.js'
``*
© 2014-25 Lloyd Brookes \
Test suite by test-runner. Documented by jsdoc-to-markdown.