export function isNumber(x) {
   return typeof x === 'number'
}

export function allNumbers(args) {
   for (let i = 0; i < args.length; ++i) {
      if (!isNumber(args[i])) return false
   }
   return true
}

export function oneNumber(args) {
   return args.length === 1 && isNumber(args[0])
}

export default function create(pmath) {
   return pmath('number', [() => true, x => Number(x)])
}