"do Tap"

gistfile1.rb

def do_each(hash)
  result = {}
  hash.each { |key, value| result[key] = do_something(value) }
  result
end

def do_inject(hash)
  hash.inject({}) { |result, pair| result[pair.first] = do_something(pair.last); result }
end

def do_tap(hash)
  {}.tap do |result|
    hash.each { |key, value| result[key] = do_something(value) }
  end
end

def do_map(hash)
  Hash[hash.map { |key, value| [key, do_something(value)] }]
end