How to avoid NoMethodError for missing elements in nested hashes, without repeated nil checks?

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Ruby 2.3.0 introduced a new method called dig on both Hash and Array that solves this problem entirely.

name = params.dig(:company, :owner, :name)

It returns nil if the key is missing at any level.

If you are using a version of Ruby older than 2.3, you can use the ruby_dig gem or implement it yourself:

module RubyDig
  def dig(key, *rest)
    if value = (self[key] rescue nil)
      if rest.empty?
        value
      elsif value.respond_to?(:dig)
        value.dig(*rest)
      end
    end
  end
end

if RUBY_VERSION < '2.3'
  Array.send(:include, RubyDig)
  Hash.send(:include, RubyDig)
end

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