Number_Value : sub_class_of : Type_Item

This item represents a particular type of constant value that can be used as the object of connections. For example, in the statement "SallySinger sPercentileRankingInClassIs '88.75'", the object value "88.75" is a number (in this point, a floating-point number with a fractional part). The system will accept any number that can be typed, and attempts to parse number formats that include non-number characters (such as the "e" or "E" in scientific notation). The system does not have a way to represent fractions, imaginary numbers, repeating digits, or significant figures.

This relationship is used to connect two items, both representing classes, indicating that the subject item is a sub-class of the object item. For example, the connection "Ships is a SubClass-Of Vehicles" links the two class items, and makes the statement that "Ships" are a more specific kind of "Vehicles". Once this connection is established, the system will behave as if everything that is true about "Vehicles" is also true for "Ships" (although not vice-versa). For example, if another property is defined such that its object items are required to be instances of the "Vehicles" class, then having this connection allows instances of "Ships" to be used as well. But, another property whose objects are required to be "Ships" is not affected, and other "Vehicles" still cannot be used.

This category item is the class that contains all items representing possible "types" for the values of property objects that are constants (rather than other items). For example, in the connection "SallySinger sBirthdayIs 'March 10, 1977'", the object of the "sBirthdayIs" property is a date constant. The type for data constants is represented in the system by the item "Date_Value", which is one of the members of this class. All of the constant types that the system is capable of handling are represented by members of "Type_Item". (Note that, if the type of information you want to use as a constant object doesn't have a matching "Type_Item" member, you can use the generic "String_Value" type.)