Using Caché Objects - InterSystems Documentation

You can override a property's default accessor methods. In the last screen of the New Property
Wizard in the Studio, you can select the check boxes for creating a custom Get method, Set,
or both; if so the Studio creates signatures for the custom methods. Within the custom methods,
you can perform any special processing that your application requires.
Invoking a Set method from within a Set method creates a recursive series of references that
results in a stack overflow; likewise for Get methods. To avoid this situation, Caché provides
a mechanism for working with a property's instance value that circumvents the accessor
methods. This mechanism refers to a property's instance variable directly by using syntax of
i%, where is the name of property being accessed.
For example, to directly set the value of the LName instance variable, the “i%” syntax is:
Set i%LName = "Blutarsky"
i% Syntax
This directly sets “Blutarsky” as the value of the instance variable LName, bypassing the
LNameSet accessor. The advantage of this mechanism is that it gives you direct control over
the instance variable's value. This must be used with caution and only under appropriate circumstances,
since the ability to circumvent any checking done in the property's Set method
can result in properties containing non-valid values.
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