ruby-on-rails - 缩短 .each do 循环

Question

我有这个循环:

data.each do |variant|
code = prices[variant["vcode"].to_sym]
  if code.nil?
    reg = sell = sale = " "
  else
    reg = code[:reg]
    sell = code[:sell]
    sale = code[:sale]
  end
  variant["reg"] = reg
  variant["sell"] = sell
  variant["sale"] = sale

现在，我想缩短代码，就像我之前对 reg = sell = sale = "" 所做的那样:

reg = " "
sell = " "
sale = " "

我也想做

reg = code[:reg]
sell = code[:sell]
sale = code[:sale]

和

  variant["reg"] = reg
  variant["sell"] = sell
  variant["sale"] = sale

我试过这个:

  def price_values
    %i[reg sell sale]
  end

并替换

reg = code[:reg]
sell = code[:sell]
sale = code[:sale]

与

reg, sell, sale = code[price_values]

但它返回nil。我做错了什么？

Answer 1

data.each do |variant|
  code = prices[variant["vcode"].to_sym]
  %w|reg sell sale|.each do |e|
    variant[e] = code.nil? ?  " " : code[e.to_sym]
  end
end

或者，更好的是，使用默认哈希函数。

data.each do |variant|
  code =
    prices[variant["vcode"].to_sym] ||
    Hash.new { |h, k| h[k] = " " }

  %w|reg sell sale|.each do |e|
    variant[e] = code[e.to_sym]
  end
end