PrF UG slots value type menu
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The Value Type Menu
The Value Type menu in the Slot Editor allows you to select the slot value type, which determines the kind of values that the slot may hold. When a value type of Class, Instance, or Symbol is selected, an additional pane appears below the Value Type menu.
The following value types are available:
Any: the slot can take any of the values on the menu.
Boolean: a logical, Boolean value; i.e., a value that is either true or false
Class: the slot takes one or more classes as values
Float: the slot has a floating-point number as a value
Instance: the slot takes one or more instances as values
Integer: the slot takes an integer as a value
String: the slot takes ASCII text strings as values
Symbol: the slot takes values from a list of strings you define