Syntax

$object.add(`$attr`, $value)

$object.add(`$attr`, $index, $value)

Description

Appends a value to a set attribute attr of an object.

Can also be done with the set() function by concatenating the old set of attributes with the new value:

$object.set(`$attr`, concat(object.get(`$attr`).subList(0, $index), $value, object.get(`$attr`).subList($index)))

Elements of the attribute the user may not discover are kept. The index refers to the list the user sees (without the elements the user may not discover). The added values must be objects the user may discover.

Parameter

Name	Type	Description	Mandatory	Default
object	Business object	The object to which a new value in an attribute should be added.	yes
attr	String	The attribute literal of the attribute to which a value is to be added. The attribute must be a set. Attributes with only single values will generate an error message, since nothing can be added, only set (cf. Set attribute value).	yes
index	number	The position in the set attribute where the new value is to be inserted.	no	index = object.get(`$attr`).size() In this case the new value will be inserted at the end of the set.
value	Number/string/boolean/business object/set	The new value to add to the object's attribute.	yes

Examples

Insert new child

	{
   parent = new(`my.module:MyType`);
   child = new(`my.module:MyType`);
   $parent.add(`my.module:MyType#children`, $child);
   $parent.get(`my.module:MyType#children`);
}

Output: A set with the element [child].

After two objects have been created, one object has been added to the other as a child.

Insert new child at index

	{
   parent = new(`my.module:MyType`);
   child1 = new(`my.module:MyType`);
   child2 = new(`my.module:MyType`);
   child3 = new(`my.module:MyType`);
   $parent.add(`my.module:MyType#children`, $child1);
   $parent.add(`my.module:MyType#children`, $child3);
   $parent.add(`my.module:MyType#children`, 1, $child2);
   $parent.get(`my.module:MyType#children`);
}

Output: A set with the elements [child1, child2, child3].

The object child2 is inserted by specifying the index between child1 and child3.