Explains how all Hashes in an Array can be merged.

merging_hashes_explained.rb

[{:a => 'alpha'}, {:b => 'beta'}, {:c => 'charlie'}].map(&:to_a)
#=> [[[:a, "alpha"]], [[:b, "beta"]], [[:c, "charlie"]]]

flat_array = [{:a => 'alpha'}, {:b => 'beta'}, {:c => 'charlie'}].map(&:to_a).flatten
#=> [:a, "alpha", :b, "beta", :c, "charlie"]

Hash[*flat_array]
#=> {:a=>"alpha", :b=>"beta", :c=>"charlie"}


# Bringing us to --
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'}