class Hash

# File lib/hash-polyfill.rb, line 2
def compact
  reject do |key, value|
    value.nil?
  end
end

# File lib/hash-polyfill.rb, line 8
def compact!
  reject! do |key, value|
    value.nil?
  end
end

# File lib/hash-polyfill.rb, line 28
def reject_values
  return enum_for(:reject_values) unless block_given?
  reject do |key, value|
    yield(value)
  end
end

# File lib/hash-polyfill.rb, line 35
def reject_values!
  return enum_for(:reject_values!) unless block_given?
  reject! do |key, value|
    yield(value)
  end
end

# File lib/hash-polyfill.rb, line 14
def select_values
  return enum_for(:select_values) unless block_given?
  select do |key, value|
    yield(value)
  end
end

# File lib/hash-polyfill.rb, line 21
def select_values!
  return enum_for(:select_values!) unless block_given?
  select! do |key, value|
    yield(value)
  end
end

# File lib/hash-polyfill.rb, line 59
def slice(*values)
  result = {}
  values.each do |key|
    result[key] = self[key] if has_key?(key)
  end
  result
end

# File lib/hash-polyfill.rb, line 67
def transform_keys
  return enum_for(:transform_keys) unless block_given?
  result = {}
  each do |key, value|
    result[yield(key)] = value
  end
  result
end

# File lib/hash-polyfill.rb, line 42
def transform_values
  return enum_for(:transform_values) unless block_given?
  result = {}
  each do |key, value|
    result[key] = yield(value)
  end
  result
end

# File lib/hash-polyfill.rb, line 51
def transform_values!
  return enum_for(:transform_values!) unless block_given?
  each do |key, value|
    self[key] = yield(value)
  end
  self
end