ruby判断数字类型函数

data = gets.chomp

data.is_a?(Integer)判断是否为整数Integer类型

data.is_a?(Float)浮点数类型

data.is_a?(Numeric)是否数字的判断

for instance:

require 'prime'


def first_n_primes(n)
  # Check for correct input!
  "n must be an integer" unless n.is_a? Integer
  "n must be greater than 0" if n <= 0


  # The Ruby 1.9 Prime class makes the array automatically!
  prime = Prime.instance
  prime.first n
end


first_n_primes(10)