TypeScript typeof utility helper with no dependencies. Provides type guards for all common types.
npm install ts-util-is
Import everything:
import * as util from 'ts-util-is';
const value: string | string[] = 'hey there';
if (util.isArray(value)) {
console.log(value.split(' ')); // `value` is string[]
}Import only what you need:
import { isArray, isString } from 'ts-util-is';
const value: string | string[] = 'hello again';
if (isArray(value)) {
console.log(value.split(' ')); // `value` is string
}isArray()isBase64()isBoolean()isDate()isDateValid()isDefined()isError()isFunction()isGuid()isInfinity()isNegativeNumber()isNull()isNil()isNonEmptyString()isNonZeroNumber()isNumber()isObject()isPlainObject()isPositiveNumber()isRegExp()isString()isSymbol()isUndefined()isInstance()