Use switch like if-else in a flexible way

flexible_switch.js

function checkAge(age){
  switch(true){               // Set boolean first
    case (age > 18):
      console.log('case 1')
      break
    case (age == 18):
      console.log('case 2')
      break
    case (age < 18):
      console.log('case 3')
      break
    default:
      console.log("It didn't match any one")
      break
  }
}

// main 
checkAge(12) // case 3