HasRuntimeCheck

Since 1.2.0

Check if a type has a runtime check function.

Signature

type HasRuntimeCheck<T> = T extends string | number | boolean | symbol | bigint | null | undefined
  ? true
  : T extends Array<infer _>
    ? true
    : T extends Map<infer _, infer _>
      ? true
      : T extends Set<infer _>
        ? true
        : T extends Date
          ? true
          : false

Parameters

Parameter	Description
T	The type to check

Description

Determines if a type can be checked at runtime using JavaScript's typeof or instanceof operators. Primitive types, arrays, maps, sets, and dates have built-in runtime checks.

Examples

Basic Usage

import type { HasRuntimeCheck } from 'uni-types'

type CheckString = HasRuntimeCheck<string>  // true
type CheckObject = HasRuntimeCheck<{ a: string }>  // false

With Built-in Types

import type { HasRuntimeCheck } from 'uni-types'

type CheckArray = HasRuntimeCheck<number[]>  // true
type CheckDate = HasRuntimeCheck<Date>  // true
type CheckMap = HasRuntimeCheck<Map<string, number>>  // true

Related

• RuntimeGuard - Define type guard function
• GuardedType - Extract type from guard