How to elegantly symbolize_keys for a 'nested' hash

Question

Consider the following code:

  hash1 = {\"one\" => 1, \"two\" => 2, \"three\" => 3}
  hash2 = hash1.reduce({}){ |h, (k,v)| h.merge(k => hash1) }
  ha         


        

Answer 1

I can suggest something like this:

class Object
  def deep_symbolize_keys
    self
  end
end

class Hash
  def deep_symbolize_keys
    symbolize_keys.tap { |h| h.each { |k, v| h[k] = v.deep_symbolize_keys } }
  end
end

{'a'=>1, 'b'=>{'c'=>{'d'=>'d'}, e:'f'}, 'g'=>1.0, 'h'=>nil}.deep_symbolize_keys
# => {:a=>1, :b=>{:c=>{:d=>"d"}, :e=>"f"}, :g=>1.0, :h=>nil} 

You can also easily extend it to support Arrays:

class Array
  def deep_symbolize_keys
    map(&:deep_symbolize_keys)
  end
end

{'a'=>1, 'b'=>[{'c'=>{'d'=>'d'}}, {e:'f'}]}.deep_symbolize_keys
# => {:a=>1, :b=>[{:c=>{:d=>"d"}}, {:e=>"f"}]}