In an attempt to be as language-neutral as possible, this book presents very little code. Prototypes for the methods of ODPart, where presented, are in the SOM Interface Definition Language (IDL). As an example of what IDL prototypes look like, here is the prototype for the AddProperty method of ODStorageUnit:
ODStorageUnit AddProperty (in ODPropertyName propertyName);
Note the directional attribute ("in") that precedes the type designation of the single parameter.