.. highlightlang:: us

.. index:: obj_set_parent

.. _obj_set_parent:

obj_set_parent
==============

.. us.tag  obj_set_parent NOTREADYENGLISH obj New410 Changed5502

:ref:`obj_set_parent` sets the parent object.

.. function::  bool = obj_set_parent(obj, parent)

.. us.return

**Return Value**

*bool* is TRUE (1), if the function could set the parent successfully.

.. us.params

**Parameters**

.. uparam:: obj

   *obj* is the object created with :ref:`obj_create`.

.. uparam:: parent

   *parent* is an object created with :ref:`obj_create`.

.. us.comment

**Comment**

The :ref:`obj_set_parent` function copies all key-value pairs from *parent*  to 
*obj* and saves a reference of the parent object. Example:: 

   o = [. a = 1,
          b = 2
   ];
   o1 = [. c = 3,
           d = 4
   ];
   o1.set_parent(o);

*o1* contains the variables a, b, c, d. Instead of ``set_parent`` the 
following syntax can be used to set the parent object::

   o1 = [. __parent__ = o;
           c = 3,
           d = 4
   ];

If *o* contains pointers to objects, only the pointers will be copied. Before
UniPlot R2013.2 a copy of all objects were created.

*obj* "inherits" all properties of its *parent*. The child object will also
inherit all parent methods. 

If ``obj.name(1,2)`` is invoked and *obj* does not possess a method ``name``, the
parent function will be invoked ``obj.parent.name(1,2)``. If the parent does not
possess a function a method ``name`` its parent object is invoked
``obj.parent.parent.name(1,2)`` and so on.

.. us.history

**History**

.. list-table::
   :header-rows: 1

   * - Version
     - Description
   * - R2013.2
     - Only references to objects are copied. See above.
   * - 4.1.0
     - New.

.. seealso::
   :ref:`overview-uniscript-objects`,
   :ref:`obj_parent`,
   :ref:`obj_set_methods`

:sub:`id-1665813`