Using Caché Objects - InterSystems Documentation

Property Accessors
7.4 Property Accessors
The Caché dot syntax for referring to properties is an interface for a set of accessor methods
to retrieve and set values. For each property, whenever the code refers to oref.Prop (where
oref is an object and Prop is a property), it is executed as if a system-supplied PropGet or
PropSet method were invoked. For example:
Set person.DOB = x
acts as if the following method was called:
Do person.DOBSet(x)
while:
Write person.Name
acts like:
Write person.NameGet()
It is important to point out that in most cases, there are no actual PropGet and PropSet
methods; access for simple properties is implemented directly within the Caché virtual machine
for optimal performance. You can, however, provide PropGet and PropSet methods for a
specific property. In this case, these accessor methods will be invoked at runtime automatically.
Typically, every property has process-private, in-memory storage allocated for it. The systemprovided
property accessors use this storage directly. Note that this object storage is not held
in the local variable symbol table and is not affected by the Kill command.
If you need to access the in-memory stored value of a property from within an instance method
of an object, you can use the following in-memory value syntax:
Set i%Name = "Carl"
This directly sets “Carl” as the in-memory value of the property Name, bypassing the NameSet
accessor (if present).
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