Contents

• About
• Features
• Installation
• Documentation
  • Tree
  • Import
  • Methods
  • Types

About

Infer types.

Features

• Infers multiple types
• Infers integer and float types
• Infers the type from a string
• There are simple type converters

Installation

You can install it as follows.

# NPM
npm add typof

# PNPM
pnpm add typof

# Yarn
yarn add typof

# Bun
bun add typof

# Deno
deno add typof

Documentation

Tree

Briefly as follows.

typof
│
├── typof(value)
├── string(value)
├── number(value)
├── integer(value)
├── float(value)
├── boolean(value)
├── date(value)
├── object(value)
├── array(value)
├── _null(value)
└── _undefined(value)

typof/types
│
├── type Types
└── type UnknownObject

Import

Briefly as follows.

import { typof } from 'typof';

Methods

typof(value)

Infer types.

Parameter	Type	Default	Description
value	Unknown		Value to infer types.

returns Types[]

Example:

// Tests are as follows. (Is this an integer?)
if (typof(0).includes('integer')) console.log('This is an integer.');

// Index zero always ensures reliable type checking. As the index increases, species depth also increases.
if (typof('0.5')[0] === 'string') console.log('This is a string.');

typof('test'); // ['string']

typof('0'); // ['string', 'number', 'integer']
typof(0); // ['number', 'integer']

typof('0.5'); // ['string', 'number', 'float']
typof(0.5); // ['number', 'float']

typof('true'); // ['string', 'boolean']
typof(true); // ['boolean']

typof('2025-01-01'); // ['string', 'date']
typof(new Date('2025-01-01')); // ['date', 'object']

typof('{"key":"value"}'); // ['string', 'object']
typof({ key: 'value' }); // ['object']

typof('["test"]'); // ['string', 'array']
typof(['test']); // ['array']

typof('null'); // ['string', 'null']
typof(null); // ['null']

typof('undefined'); // ['string', 'undefined']
typof(undefined); // ['undefined']

string(value)

Convert to string.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns String

Example:

string(0.5); // '0.5'
string(true); // 'true'
string(new Date('2025-01-01')); // '2025-01-01T00:00:00.000Z'
string({ key: 'value' }); // '{"key":"value"}'
string(['test']); // '["test"]'
string(null); // 'null'
string(undefined); // 'undefined'

number(value)

Convert to number.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Number

Example:

number('0.5'); // 0.5
number(0.5); // 0.5
number('test'); // NaN

integer(value)

Convert to integer.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Number

Example:

integer('0.5'); // 0
integer(0.5); // 0
integer('test'); // NaN

float(value, fraction_digits)

Convert to float.

Parameter	Type	Default	Description
value	Unknown		Value to convert.
fraction_digits	Number		Fraction digits.

returns String | Value

Example:

float('0', 2); // '0.00'
float(0, 2); // '0.00'
float(0.5555, 2); // '0.55'
float(0.5555, 4); // '0.5555'
float('test', 2); // 'test'

boolean(value)

Convert to boolean.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Boolean | Value

Example:

boolean('true'); // true
boolean(true); // true
boolean('test'); // 'test'

date(value)

Convert to date.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Date | Value

Example:

date('2025-01-01'); // 2025-01-01T00:00:00.000Z
date(new Date('2025-01-01')); // 2025-01-01T00:00:00.000Z
date('test'); // 'test'

object(value)

Convert to object.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns UnknownObject | Value

Example:

object('{"key":"value"}'); // { key: 'value' }
object('["test"]'); // '["test"]'

array(value)

Convert to array.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Unknown[] | Value

Example:

array('["test"]'); // ['test']
array('{"key":"value"}'); // '{"key":"value"}'

_null(value)

Convert to null.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Null | Value

Example:

_null('null'); // null
_null(null); // null
_null('test'); // 'test'

_undefined(value)

Convert to undefined.

Parameter	Type	Default	Description
value	Unknown		Value to convert.

returns Undefined | Value

Example:

_undefined('undefined'); // undefined
_undefined(undefined); // undefined
_undefined('test'); // 'test'

Types

Type
Types
UnknownObject