.. _functx_if-empty:

===============
functx:if-empty
=============== 

The first argument if it is not blank, otherwise the second argument

Description
~~~~~~~~~~~
The functx:if-empty function is useful for providing default values in case an 
element or attribute is empty or non-existant. An element is considered empty if 
it does not have any content (e.g. <value></value> or <value/>). An attribute is 
considered empty if its value is a zero-length string (e.g. value=""). If $node 
is not empty, this function returns the typed value of the node. If it is empty, 
or it is non-existent (equal to the empty sequence), it returns the value 
$value.

Note: This function is similar to the eg:if-empty function provided in the 
XQuery 1.0 and XPath 2.0 Functions and Operators document. However, this 
function differs in that it supports attribute nodes and atomic values.

.. list-table::
   :widths: 40 60
   :header-rows: 1

   * - **Parameters**
     - **Description**
   * - arg:item()
     - the node that may be empty
   * - value:item()
     - the item(s) to use if the node is empty

Examples
~~~~~~~~
.. list-table::
   :widths: 50 50
   :header-rows: 1

   * - **XPath**
     - **Results**
   * - functx:if-empty($in-xml//price[1], 0)
     - 29.99
   * - functx:if-empty($in-xml//price[3], 0)
     - 0
   * - functx:if-empty($in-xml//price[99], 0)
     - 0
   * - functx:if-empty($in-xml//price[1]/@discount, 0)
     - 10.00
   * - functx:if-empty($in-xml//price[3]/@discount, 0)
     - 0
   * - functx:if-empty($in-xml//price[4]/@discount, 0)
     - 0

See Also
~~~~~~~~

.. toctree::
   :titlesonly:
   :glob:

* :ref:`functx_if-absent`.
* :ref:`functx_all-whitespace`.
* :ref:`empty`.