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Package detail

@js-utilities/typecheck

vitalishapovalov2.4kMIT0.1.6TypeScript support: included

Utility library for javascript type checking.

type checking, type predicates, isCallable, isFunction, isArrowFunction, isArray, isObject, isBoolean, isUndefined, isNumber, isString, isSymbol, isNull, isMap, isSet, isWeakSet, isWeakMap

readme

Type checking library

npm version Build Status

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>

License

MIT License

changelog

0.1.6

No code changes. Re-build the lib using latest ts/rollup/optimizers.

0.1.5

BROKEN BUILD. Please, use 0.1.6 instead.

0.1.4

Improvement for isWeakMap, isWeakSet, isSet, isMap, isSymbol.

0.1.3

  • added isPromise type check
  • fixed isBoolean