class FalseClass

# File activesupport/lib/active_support/core_ext/object/blank.rb, line 65
def blank?
  true
end

false пусто:

false.blank? # => true

@return [true]

# File activesupport/lib/active_support/core_ext/object/duplicable.rb, line 53
def duplicable?
  false
end

false не дублируемый:

false.duplicable? # => false
false.dup         # => TypeError: can't dup FalseClass

# File activesupport/lib/active_support/core_ext/object/to_query.rb, line 32
def to_param
  self
end

Возвращает self.