LINQ in Ruby

gistfile1.rb

class Query
  undef select
  def method_missing(id, &block)
    if block
      instance_variable_set("@#{id}", block)
    else
      instance_variable_get("@#{id}")
    end
  end
end

def from(enum, &block)
  query = Query.new
  query.instance_eval(&block)
  result = enum.
    select { |i| i.instance_eval(&query.where) }.
    sort_by { |i| i.instance_eval(&query.order) }.
    map { |i| i.instance_eval(&query.select) }
end

names = ["Alf", "Peter", "Heinz", "Udo"]

p(from(names) do
  where { length == 5 }
  order { downcase }
  select { upcase }
end)