006.Arguments trong Ruby.

Một vài tóm tắt nho nhỏ về parameter của Ruby.

Required parameters

def chocolate(number_of_milk_packets)
  “This will be good with #{number_of_milk_packets} packets”
end
chocolate()
# ArgumentError: wrong number of arguments (given 0, expected 1)
chocolate(1,2,3)
# ArgumentError: wrong number of arguments (given 3, expected 1)

Default parameters

def chocolate(number_of_milk_packets=1) #method with default parameter
  “This will be good with #{number_of_milk_packets} milk packets”
  end
chocolate()
# This will be good with 1 milk packets
chocolate(7)
# This will be good with 7 milk packets

Optional parameters

def chocolate(*number_of_milk_packets) #with optional parameter
  “This will be good with #{number_of_milk_packets} packets”
end
chocolate(5,9,2)
# “This will be good with [5,9,2] packets”

Keyword parameters

def testing(d = 1)
  p d
end
testing()
# 1
testing(d: 2)
# 2

Other case

def testing(**x)
  p x
end
testing(x: 1)
# {:x=>1}

Thực sự méo biết để làm gì

class Food
  def nutrition(vitamins, minerals)
    puts vitamins
    puts minerals
  end
end
class Bacon < Food
  def nutrition(*)
    super
  end
end
bacon = Bacon.new
bacon.nutrition("B6", "Iron")
# B6
# Iron