Function isError

lib/internal/util.js:99–104

(e)

}

function isError(e) {
  // An error could be an instance of Error while not being a native error
  // or could be from a different realm and not be instance of Error but still
  // be a native error.
  return isNativeError(e) || FunctionPrototypeSymbolHasInstance(Error, e);
}

// Keep a list of deprecation codes that have been warned on so we only warn on
// each one once.