:right-sidebar: True

Cache
===================================================================

.. currentmodule:: gi.repository.GLib





.. deprecated:: 2.32

   Use a :obj:`~gi.repository.GLib.HashTable` instead


.. class:: Cache(*args, **kwargs)
   :no-contents-entry:






A ``GCache`` allows sharing of complex data structures, in order to
save system resources.

``GCache`` uses keys and values. A ``GCache`` key describes the properties
of a particular resource. A ``GCache`` value is the actual resource.

``GCache`` has been marked as deprecated, since this API is rarely
used and not very actively maintained.




Methods
-------

.. rst-class:: interim-class

.. class:: Cache
   :no-index:


   .. method:: destroy() -> None

      Frees the memory allocated for the :obj:`~gi.repository.GLib.Cache`\.

      Note that it does not destroy the keys and values which were
      contained in the :obj:`~gi.repository.GLib.Cache`\.





      .. deprecated:: 2.32

         Use a :obj:`~gi.repository.GLib.HashTable` instead






   .. method:: insert(key: ~typing.Any = None) -> ~typing.Any | None

      Gets the value corresponding to the given key, creating it if
      necessary. It first checks if the value already exists in the
      :obj:`~gi.repository.GLib.Cache`\, by using the ``key_equal_func`` function passed to
      :func:`~gi.repository.GLib.Cache.new`. If it does already exist it is returned, and its
      reference count is increased by one. If the value does not currently
      exist, if is created by calling the ``value_new_func``\. The key is
      duplicated by calling ``key_dup_func`` and the duplicated key and value
      are inserted into the :obj:`~gi.repository.GLib.Cache`\.





      .. deprecated:: 2.32

         Use a :obj:`~gi.repository.GLib.HashTable` instead



      :param key: a key describing a :obj:`~gi.repository.GLib.Cache` object




   .. method:: key_foreach(func: ~typing.Callable[[~typing.Any, ~typing.Any, ~typing.Any], None], user_data: ~typing.Any = None) -> None

      Calls the given function for each of the keys in the :obj:`~gi.repository.GLib.Cache`\.

      NOTE ``func`` is passed three parameters, the value and key of a cache
      entry and the ``user_data``\. The order of value and key is different
      from the order in which :func:`~gi.repository.GLib.HashTable.foreach` passes key-value
      pairs to its callback function !





      .. deprecated:: 2.32

         Use a :obj:`~gi.repository.GLib.HashTable` instead



      :param func: the function to call with each :obj:`~gi.repository.GLib.Cache` key

      :param user_data: user data to pass to the function




   .. method:: remove(value: ~typing.Any = None) -> None

      Decreases the reference count of the given value. If it drops to 0
      then the value and its corresponding key are destroyed, using the
      ``value_destroy_func`` and ``key_destroy_func`` passed to :func:`~gi.repository.GLib.Cache.new`.





      .. deprecated:: 2.32

         Use a :obj:`~gi.repository.GLib.HashTable` instead



      :param value: the value to remove


      :return: 0 if the file was successfully removed, -1 if an error
            occurred



   .. method:: value_foreach(func: ~typing.Callable[[~typing.Any, ~typing.Any, ~typing.Any], None], user_data: ~typing.Any = None) -> None

      Calls the given function for each of the values in the :obj:`~gi.repository.GLib.Cache`\.





      .. deprecated:: 2.10

         The reason is that it passes pointers to internal
            data structures to ``func``\; use :func:`~gi.repository.GLib.Cache.key_foreach` instead



      :param func: the function to call with each :obj:`~gi.repository.GLib.Cache` value

      :param user_data: user data to pass to the function