InvalidValue class

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An InvalidValue exception indicates that a given value is not associated with a given enumeration. For example:

enumeration foo public attribute x is float inverse fromX value y (3) allow ordinal end public end enumeration %f is enumeration foo %f = fromString('Y') printText {~=%f} %f = fromX(3) printText {~=%f} try %f = fromString('z') catch invalidValue print 'z is not a foo enumeration string value' end try try %f = fromX(1) catch invalidValue print '1 is not a foo enumeration x attribute value' end try %f = fromOrdinal(1) printText {~=%f} %f = fromOrdinal(3)

The result of the above fragment is:

%f=y %f=y z is not a foo enumeration string value 1 is not a foo enumeration x attribute value %f=y *** 1 CANCELLING REQUEST: MSIR.0750: Class Foo, function FromOrdinal: InvalidValue exception: 3 is not a valid ordinal number for class foo ...

The InvalidValue exception class has no properties. It is simply a notification that a valid attempt found no values that matched the given string or number.

To produce an InvalidValue exception yourself, you typically use a User Language Throw statement with an InvalidValue New constructor. This statement must be issued from within a method, and it can only be caught by the code that calls the method. For example, the following statement throws an InvalidValue exception:

throw %(invalidValue):new

Remember that you catch an exception with the Catch statement; if an exception condition occurs outside a Catch for it, the request is cancelled.

The InvalidValue class is available as of Sirius Mods version 7.8.

The InvalidValue methods

The following are the available InvalidValue class methods.

NewCreate a new InvalidValue object

The methods in the class are described in the subsections that follow. In addition:

New constructor

Create a new InvalidValue object (InvalidValue class)

[Introduced in Sirius Mods 7.8]

This Constructor generates an instance of an InvalidValue exception. The New method format follows:


%invalidValue = [%(InvalidValue):]New

Syntax terms

%invalidValue A reference to an instance of an InvalidValue object.
[%(InvalidValue):] The class name in parentheses denotes a Constructor. See Usage notes, below, for more information about invoking an InvalidValue Constructor.

Usage notes

  • As described in Using New or other Constructors, New can be invoked with no object, with an explicit class name, or with an object variable in the class, even if that object is Null:

    %invalid = new %invalid = %(InvalidValue):new %invalid = %invalid:new