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The Item Class

The ITEM class is the root class of the G2 class hierarchy. For more information about G2's system-defined class hierarchy, see Chapter 13, Classes and Class Hierarchy.

The system-defined attributes that G2 provides for all items in a knowledge base are described in the following table. To avoid redundancy, they are omitted from all other attribute descriptions in this manual that pertain to items:

Attribute Description
Notes
Displays the current value of the item participation status: OK/incomplete/bad, active/inactive, and enabled/disabled. Use this attribute's value to identify a discrepancy in the knowledge that an item contains. If there are no problems with the item, G2 displays OK. If there are problems with the value of any item attribute, G2 displays BAD. If there are attributes that require values but do not yet have them, G2 displays INCOMPLETE.
Allowable values:
OK
BAD
INCOMPLETE

Default value:
Varies, depending on the class of the item.
Notes:
You cannot edit this attribute, but you can refer to it programmatically in an expression, and by using the phrase with notes in a filter expression within the Inspect facility. For information on the status of items, see Participation Status.


Names
Contains one or more names for an item. G2 does not require that this attribute have a value. For example, a short name can identify the item in a schematic, while a long name refer to the item in a rule or other statement.
Allowable values:
Any unreserved symbol
Default value:
none
Notes:
Items of some system-defined classes do not offer a Names attribute. See Understanding Item Inheritance. If two connection posts have the same name, G2 considers them to be connected.


Item-configuration
Contains one or more configuration statements that apply to this item and to all items below it in the workspace hierarchy.
Allowable values:
See Declaring Configurations for Items.
Default value:
none

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