处理嵌套数组

Question

给出以下代码(我显示一些有关预订的统计信息):

statistics = [["Germany", "EUR"], 23], [["Germany", "USD"], 42], [["Spain", "EUR"], 17]

statistics.each do |country_and_currency, number_of_bookings|
  country, currency = country_and_currency # <-- Ugly.

  puts "There are #{number_of_bookings} in #{currency} in #{country}"
end

这country_and_currency部分非常难看.我试过了... do |*(country, currency), number_of_bookings|,但这没用.

有没有一种优雅的方法来处理这个嵌套数组而不使用country_and_currency变量？

Answer 1

是的,这是可能的:

statistics = [
               [["Germany", "EUR"], 23], 
               [["Germany", "USD"], 42], 
               [["Spain", "EUR"], 17]
             ]

statistics.each do |(country, currency), number_of_bookings|
  puts "There are #{number_of_bookings} in #{currency} in #{country}"
end

产量

There are 23 in EUR in Germany
There are 42 in USD in Germany
There are 17 in EUR in Spain