Inserts value a into the list b, but only if it is not already contained, otherwise the list remains unchanged.

The return value always is value a.

Parameters

Parameter	Description
a	Value to be added.
b	Name of the list (if the list does not exist, it is created). Default: "default".
c	(optional) "true", if values with set Empty Flag should not be added to the list. Default: "false". Note: Please note that if the parameter is set to "false", values with a set Empty Flag (hidden values) are added to the list.

Example

Parameter a	Parameter b	Parameter c	Result	Value added to list
Hallo (Empty Flag: false)	MyList		Hallo	Yes.
Hallo (Empty Flag: false)	MyList		Hallo	No, because value already exists in list.
Hello (Empty Flag: true)	MyList	false	Hello	Yes.
Hällo (Empty Flag: true)	MyList	true	Hällo	No.