INCLUDE_ONCE

Same behavior as the INCLUDE directive, except that the file will not be included more than once.
Note, that the "content" attribute works only with INCLUDE.

Attributes brief detailed show all inherited

	Name	Description	Default
Inherited from include
	file	Path to the XML file to includeThe file to include has to be a valid XML file with a single root element	empty
	ignore_missing	When set to true, no error is thrown if the file is missingBeware that this may cause errors that may be difficult to catch (missing objects...) if not used with care	false

	Name	Value type	Default	Description	Comment
Inherited from include
	file	Valid file path to XML file	empty	Path to the XML file to include	The file to include has to be a valid XML file with a single root element
	ignore_missing	boolean	false	When set to true, no error is thrown if the file is missing	Beware that this may cause errors that may be difficult to catch (missing objects...) if not used with care