中间步骤的局部变量

Question

嗨,我想知道是否有人可以向我解释为什么用以下代码编写的地图函数是按照其编写的方式编写的.具体来说,我们需要做什么

results = letters.map do |letter| encrypted_letter = encrypt_letter(letter) 

而不只是做

results = letters.map do |letter| encrypt_letter(letter)

---

class Encryptor
    def cipher
    {"a" => "n", "b" => "o", 'c' => 'p', 'd' => 'q',
           'e' => 'r', 'f' => 's', 'g' => 't', 'h' => 'u',
         'i' => 'v', 'j' => 'w', 'k' => 'x', 'l' => 'y',
         'm' => 'z', 'n' => 'a', 'o' => 'b', 'p' => 'c',
         'q' => 'd', 'r' => 'e', 's' => 'f', 't' => 'g',
         'u' => 'h', 'v' => 'i', 'w' => 'j', 'x' => 'k',
         'y' => 'l', 'z' => 'm'}
    end

    def encrypt_letter(letter)
        lowercase_letter = letter.downcase
        cipher[lowercase_letter]
    end

    def encrypt(string)
        letters = string.split("")
        results = letters.map do |letter|
            encrypted_letter = encrypt_letter(letter)
        end
        results.join
    end

    def decrypt_letter(letter)
        lowercase_letter = letter.downcase
        cipher.key(lowercase_letter)
    end

    def decrypt(string)
        letters = string.split("")
        results = letters.map do |letter|
        decrypted_letter = decrypt_letter(letter)
        end

        results.join
    end

end

Answer 1

没理由; 变量立即被丢弃.

我认为它的误导性和无意识性在它之上.

大多数代码看起来有点冗长,例如:

def encrypt(string)
    letters = string.split("")
    results = letters.map do |letter|
        encrypted_letter = encrypt_letter(letter)
    end
    results.join
end

IMO这将更像Ruby-esque更接近:

def encrypt(str)
  str.chars.collect { |c| encrypt(c) }.join
end

它可能比那更严格,或以其他方式编写,尽管其中一些是偏好问题.例如,each_with_object可以与铲运营商一起使用,但这不太"功能".

(我喜欢collect在map收集资料时,偏好,我觉得更多的沟通,如果更长的时间.)

在更多行上传播功能不会使事物可读,但它取决于上下文.对Ruby或方法链接不熟悉的人可能会被(IMO更规范的)单行混淆.