Helpers and type guards for runtime value validation in TypeScript and JavaScript. These functions check if a value is primitive, nullish, boolean, string, number, object, array, function, or falsy.

Runtime Validation

Helpers and type guards for runtime value validation in TypeScript and JavaScript. These functions check if a value is primitive, nullish, boolean, string, number, object, array, function, or falsy.

Runtime Functions

Unlike other modules, these are runtime functions that can be used in JavaScript and TypeScript for actual value validation with proper type guards. This package should be installed as a production package for access to the validators in the build and final app

Installation

npm i @halvaradop/ts-utility-types

Usage

import { isPrimitive, isNullish, isArray } from "@halvaradop/ts-utility-types/validate"

import * as validate from "@halvaradop/ts-utility-types/validate"


validate.isArray
isBoolean
isFalsy
isFunction
isNullish
isNumber
isObject
isPrimitive
isPrimitiveNullish
isString

Type Guards

`isPrimitive(value: unknown): value is Primitive`

Checks if a value is a primitive type (number, string, boolean, bigint, symbol).

import { isPrimitive } from "@halvaradop/ts-utility-types/validate"

const num = isPrimitive(42)     
const num: boolean

const str = isPrimitive("hello")     
const str: boolean

const obj = isPrimitive({})
     
const obj: boolean

`isPrimitiveNullish(value: unknown): value is PrimitiveNullish`

Checks if a value is a primitive or nullish (null or undefined).

import { isPrimitiveNullish } from "@halvaradop/ts-utility-types/validate"

const und = isPrimitiveNullish(undefined)     
const und: boolean

const str = isPrimitiveNullish("hello")     
const str: boolean

const obj = isPrimitiveNullish({})
     
const obj: boolean

`isNullish(value: unknown): value is Nullish`

Checks if a value is null or undefined.

import { isNullish } from "@halvaradop/ts-utility-types/validate"

const empty = isNullish(null)      
const empty: boolean

const und = isNullish(undefined)     
const und: boolean

const num = isNullish(0)
     
const num: boolean

`isBoolean(value: unknown): value is boolean`

Checks if a value is boolean.

import { isBoolean } from "@halvaradop/ts-utility-types/validate"

const bol = isBoolean(true)     
const bol: boolean

const str = isBoolean("true")
     
const str: boolean

`isString(value: unknown): value is string`

Checks if a value is a string.

import { isString } from "@halvaradop/ts-utility-types/validate"

const str = isString("hello")     
const str: boolean

const num = isString(123)
     
const num: boolean

`isNumber(value: unknown): value is number`

Checks if a value is numeric (including NaN).

import { isNumber } from "@halvaradop/ts-utility-types/validate"

const num = isNumber(42)     
const num: boolean

const str = isNumber("42")
     
const str: boolean

`isObject(value: unknown): value is object`

Checks if a value is a plain object (not array, not function, not nullish).

import { isObject } from "@halvaradop/ts-utility-types/validate"

const obj = isObject({})     
const obj: boolean

const arr = isObject([])     
const arr: boolean

const empty = isObject(null)
      
const empty: boolean

`isArray(value: unknown): value is unknown[]`

Checks if a value is an array.

import { isArray } from "@halvaradop/ts-utility-types/validate"

const nums = isArray([1, 2, 3])      
const nums: boolean

const obj = isArray({})
     
const obj: boolean

`isFunction(value: unknown): value is Function`

Checks if a value is a function.

import { isFunction } from "@halvaradop/ts-utility-types/validate"

const fn = isFunction(() => {})     
const fn: boolean

const num = isFunction(123)
     
const num: boolean

`isFalsy(value: unknown): boolean`

Checks if a value is falsy (null, undefined, false, 0, "").

import { isFalsy } from "@halvaradop/ts-utility-types/validate"

const num = isFalsy(0)     
const num: boolean

const str = isFalsy("hello")
     
const str: boolean

Runtime Validation

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