.. _trace:

=====
trace
===== 

Reports tracing information in an implementation-defined way

Description
~~~~~~~~~~~
The fn:trace function accepts items and a label for those items, and returns the 
items unchanged. The exact behavior of the function is implementation-dependent, 
but generally the processor puts the label and the value of the items in a log 
file or user console.

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

   * - **Parameters**
     - **Description**
   * - value:item()
     - the items to trace
   * - label:string()
     - a label to display with the trace information

Examples
~~~~~~~~
.. list-table::
   :widths: 25 25 50
   :header-rows: 1

   * - **XPath**
     - **Results**
     - **Explanation**
   * - trace($var1, 'The value of $var1 is: ')
     - The value of $var1 is: 4
     - an example of what a processor might write to a log file
.. list-table::
   :widths: 50 50
   :header-rows: 1

   * - **XPath**
     - **Results**
   * - trace($var1, 'The value of $var1 is: ')
     - The value of $var1 is: 4