gistfile1.rb

# Symbol#to_proc is already defined in Rails
class Symbol
  def to_proc
    Proc.new { |item| item.send self }
  end
end

class Array
  def to_proc
    Proc.new do |item|
      inject(item) do |mem, obj|
        mem.send(obj)
      end
    end
  end
end

p ["ID", "TITLE"].collect(&[:downcase, :to_sym]) # => [:id, :title]