Ruby不能識別`downcase`或`split`作爲定義的方法嗎？

Question

問題是用下面的代碼：

#write your code here 
def translate phrase 
    phrase = phrase.downcase.split(/ /) 
    phrase.collect! do |word| 
    word = word.split(//) 
    switched = false 
    while switched == false 
     word.each_index do |letter| 
     if word[letter] == ("a" || "e" || "i" || "o" || "u") 
      switched = true 
      word = (word[letter..-1] + word[0..(letter-1)]).join + "ay" 
     end 
     end 
    end 
    end 
    return phrase.join(" ") 
end 

puts translate("chocolate cream") 
#Should return "ocolatechay eamcray" 

當我運行此，紅寶石只返回一個空行。所以，爲了解決這個問題，我把定義加載到了repl中。該REPL返回以下錯誤：如果我從我的代碼刪除downcase

NoMethodError: undefined method `downcase' for #<RubyVM::InstructionSequence:0x000000016e8f88> 
    from /home/adc/odin-project/web-development-101/21-ruby-tdd/ruby_tdd_project/learn_ruby/04_pig_latin/pig_latin.rb:3:in `translate' 
    from /home/adc/.rvm/rubies/ruby-2.3.0/bin/irb:11:in `<main>' 

，我得到同樣的錯誤信息，只有這一次split。

這裏有什麼問題？ （我敢確信downcase和split是不這個問題。）

Answer 1

如果返回一個空字符串，因爲你不回的collect!塊內部的任何物件。返回word，它會工作：

def translate phrase 
    phrase = phrase.downcase.split(/ /) 
    phrase.collect! do |word| 
    word = word.split(//) 
    switched = false 
    while switched == false 
     word.each_index do |letter| 
     if word[letter] == ("a" || "e" || "i" || "o" || "u") 
      switched = true 
      word = (word[letter..-1] + word[0..(letter-1)]).join + "ay" 
     end 
     end 
    end 
    word 
    end 
    return phrase.join(" ") 
end 

puts translate("chocolate cream") 
#=> atechocolay amcreay 

它看起來並不像它的返回你期望什麼，但它仍然不是一個空字符串更好。

至於在控制檯的奇怪的錯誤消息，這似乎是特定於REPL（方法名translate，可能是因爲）。

Answer 2

更新1（我怎麼會寫這樣的代碼）

def translate phrase 
    phrase = phrase.downcase.split(/ /) 
    phrase.collect! do |word| 
    word = word.split(//) 

    word.each_index do |letter| 
     if ["a", "e", "i", "o", "u"].include?(word[letter]) 
     if letter == 0 
      word = word[letter..-1].join + "ay" 
     else 
      word = (word[letter..-1] + word[0..(letter-1)]).join + "ay" 
     end 

     break 
     end 
    end 

    word 
    end 

    return phrase.join(" ") 
end 

puts translate("chocolate cream") 

更新2（如果我做你的代碼的一些小的改動，使其有用）

def translate phrase 
    phrase = phrase.downcase.split(/ /) 
    phrase.collect! do |word| 
    word = word.split(//) 
    switched = false 
    while switched == false 
     word.each_index do |letter| 
     if ["a", "e", "i", "o", "u"].include?(word[letter]) 
      switched = true 
      if letter == 0 
      word = word[letter..-1].join + "ay" 
      else 
      word = (word[letter..-1] + word[0..(letter-1)]).join + "ay" 
      end 
      break 
     end 
     end 
    end 
    word 
    end 
    return phrase.join(" ") 
end 

puts translate("chocolate cream") 

說明

1. "o"==("a" || "e" || "i" || "o" || "u")

   和

   "o"== "a" || "o" == "e" || "o" == "i" || "o" == "o" || "o" == "u"

   陳述是不一樣的。第一個是假的

   （因爲("a" || "e" || "i" || "o" || "u")=="a"和"o"!="a"），因爲第二個是真實的。

2. 你需要內部的if語句

   if letter == 0 
       word = word[letter..-1].join + "ay" 
   else 
       word = (word[letter..-1] + word[0..(letter-1)]).join + "ay" 
   end 
   

   因爲當字開頭提到的任一個元音然後

   word[letter..-1] + word[0..(letter-1)]

   語句將返回兩次全詞，引起信將等於0。

3. 最後一點，你需要返回word物體自動對焦ter while循環。