fumus.utils.optional
====================

.. py:module:: fumus.utils.optional


Classes
-------

.. autoapisummary::

   fumus.utils.optional.Optional


Module Contents
---------------

.. py:class:: Optional(element)

   Container object which may (or may not) contain a non-null value


   .. py:attribute:: __slots__
      :value: ('_element',)



   .. py:attribute:: _element


   .. py:method:: empty()
      :classmethod:


      Creates empty Optional



   .. py:method:: of(element)
      :classmethod:


      Creates Optional describing given non-null value



   .. py:method:: of_nullable(element)
      :classmethod:


      Returns an Optional describing the given value, if non-null,
      otherwise returns an empty Optional



   .. py:method:: get()

      If a value is present, returns the value, otherwise raises an Exception



   .. py:property:: is_present

      Returns bool whether a value is present


   .. py:property:: is_empty

      Returns bool whether the Optional is empty


   .. py:method:: if_present(action)

      Performs given action with the value if the Optional is not empty



   .. py:method:: if_present_or_else(action, empty_action)

      Performs given action with the value if the Optional is not empty,
      otherwise calls fallback 'empty_action'



   .. py:method:: or_else(value)

      Returns the value if present, or a provided argument otherwise.
      Safe alternative to get() method



   .. py:method:: or_else_get(supplier)

      Returns the value if present, or calls a 'supplier' function otherwise.
      Safe alternative to get() method



   .. py:method:: or_else_raise(supplier=None)

      Returns the value if present,
      otherwise throws an exception produced by the exception supplying function
      (if such is provided by the user) or NoSuchElementError



   .. py:method:: map(mapper)

      If a value is present, apply the provided mapping function to it,
      and if the result is non-null, return an Optional describing the result.
      Otherwise return an empty Optional.
      (NB: if the provided mapper returns an Optional,
      the result isn't wrapped-up in an additional one)



   .. py:method:: filter(predicate)

      If a value is present, and the value matches the given predicate,
      returns an Optional describing the value, otherwise returns an empty Optional



   .. py:method:: __repr__()


   .. py:method:: __eq__(other)


   .. py:method:: __hash__()