Type checking library
A set of super-simple type checkers. Each checker returns boolean
value. Most checkers are typescript type predicates.
Installation
npm i -S @js-utilities/typecheck
Usage example
import { isCallable } from "@js-utilities/typecheck";
const a: unknown = global.value;
if (isCallable(a)) a();
Available checkers:
Checker | Return type |
---|---|
isCallable |
boolean |
isFunction |
value is Function |
isArrowFunction |
boolean |
isArray<T> |
value is T[] |
isObject<T> |
value is T |
isBoolean |
value is boolean |
isUndefined |
value is undefined |
isNumber |
value is number |
isString |
value is string |
isSymbol |
value is symbol |
isNull |
value is null |
isMap<T, U> |
value is Map<T, U> |
isSet<T> |
value is Set<T> |
isWeakSet<T> |
value is WeakSet<T> |
isWeakMap<T, U> |
value is WeakMap<T, U> |
isPromise<T> |
value is Promise<T> |