[Ruby] Merge all the hashes inside an Array into one big hash

flatten_hashes.rb

class Array
  def flatten_hashes
    Hash[*self.map(&:to_a).flatten]
  end
end

[{:a => 'alpha'}, {:b => 'beta'}, {:c => 'charlie'}].flatten_hashes
#=> {:a => 'alpha', :b => 'beta', :c => 'charlie'}