const toString = Object.prototype.toString export function is(val, type) { return toString.call(val) === `[object ${type}]` } export function isFunction(val) { return is(val, 'Function') } export function isObject(val) { return is(val, 'Object') } export function isArray(val) { return is(val, 'Array') } export function isDate(val) { return is(val, 'Date') }