.. _functx_value-union:

==================
functx:value-union
================== 

The union of two sequences of values

Description
~~~~~~~~~~~
The functx:value-union function returns the union of the values in two sequences 
in an implementation-defined order. It removes duplicates, even among the values 
that appear only in one of the sequences. This function is useful because the 
built-in union (or "|") operator only works on nodes, not atomic values.

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   :widths: 40 60
   :header-rows: 1

   * - **Parameters**
     - **Description**
   * - arg1:string()
     - the first sequence
   * - arg2:string()
     - the second sequence

Examples
~~~~~~~~
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   :widths: 50 50
   :header-rows: 1

   * - **XPath**
     - **Results**
   * - functx:value-union((1,2),(3,4))
     - (1, 2, 3, 4)
   * - functx:value-union((1,2,3),(2,3,4))
     - (1, 2, 3, 4)
   * - functx:value-union((1,2,2,3),(3,4))
     - (1, 2, 3, 4)
   * - functx:value-union((1,2,2,3),())
     - (1, 2, 3)

See Also
~~~~~~~~

.. toctree::
   :titlesonly:
   :glob:

* :ref:`functx_value-intersect`.
* :ref:`functx_value-except`.