sort.rb

placeholderA = []
placeholderB = []
fh.each do |key, value|
  case key
  when "sortdescending"
    placeholderA << "a['#{value}']"
    placeholderB << "b['#{value}']"
  when "sortascending"
    placeholderA << "b['#{value}']"
    placeholderB << "a['#{value}']"
  else
    next
  end

arr.sort { |a, b| [placeholderA] <=> [placeholderB] }

The problem is I get.
arr.sort { |a, b| ["a['price'], a['name']"] <=> ["b['price'], b['name']"] }
and not
arr.sort { |a, b| [a['price'], a['name']] <=> [b['price'], b['name']] }
How do I make not string?