import cron from '<package-name>'

const cronResult = cron('* * * * *')
if (cronResult.isValid()) {
  // !cronResult.isError()
  // valid code
} else {
  // error code
}

import cron from '<package-name>'

cron('* * * * *').isValid()

cron('* * * * *').isError()

cron('* 2,3,4 * * *').isValid()

cron('0 */2 */5 * *').isValid()