NUMBERS = [10, 20, 30, 40, 50]
 
def hash_amount
  return ObjectSpace.count_objects[:T_HASH]
end
 
def measure_hash_amount
  initially = hash_amount
 
  yield
 
  return hash_amount - initially
end
 
merged = measure_hash_amount do
  NUMBERS.inject({}) do |target, current|
    target.merge(current => 'hello')
  end
end
 
returned = measure_hash_amount do
  NUMBERS.inject({}) do |target, current|
    target[current] = 'hello'
    target
  end
end
 
puts "Hashes created using #merge: #{merged}"
puts "Hashes created using a return: #{returned}"

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