export function isDefined<T>(value: T | undefined): value is T {
  return value !== void 0
}

export function isIterable(value: object): value is Collection<unknown> {
  return Symbol.iterator in <any> value
}

export function isPlainObject(value: any) {
  return value.constructor === Object || value.constructor == null
}

export function isPromiseLike(value: any) {
  return !!value && typeof value.then === "function"
}

export function isReactElement(value: any) {
  return !!(value && value.$$typeof)
}