#ruby-201909091908.rb

module DeepDup
  module Object
    alias deep_dup dup
  end
  
  module List
    def deep_dup
      dup.tap { |list| list.map!(&:deep_dup) }
    end
  end
  
  module Dict
    def deep_dup
      dup.tap { |dict| dict.transform_values!(&:deep_dup) }
    end
  end
end

Object.include(DeepDup::Object)
Array.include(DeepDup::List)
Hash.include(DeepDup::Dict)

module DeepCompact
  module Common
    def deep_compact
      deep_dup.deep_compact!
    end
  end
  
  module List
    include Common
    
    def deep_compact!
      each { |value| value.deep_compact! if value.respond_to?(:deep_compact!) }
        .delete_if { |value| value.nil? || value.respond_to?(:empty?) && value.empty? }
    end
  end
  
  module Dict
    include Common
    
    def deep_compact!
      each_value { |value| value.deep_compact! if value.respond_to?(:deep_compact!) }
        .delete_if { |_key, value| value.nil? || value.respond_to?(:empty?) && value.empty? }
    end
  end
end

Array.include(DeepCompact::List)
Hash.include(DeepCompact::Dict)

x = [{a: 1, b: [2, 3, nil], c: [], d: {a: nil}}, 1, 2, [], [1, 2, 3], [nil, nil, []]]
x.deep_compact #=> [{:a=>1, :b=>[2, 3]}, 1, 2, [1, 2, 3]]
x #=> [{:a=>1, :b=>[2, 3, nil], :c=>[], :d=>{:a=>nil}}, 1, 2, [], [1, 2, 3], [nil, nil, []]]