Including Namespaces in Classes
A Class may import methods from one or more plain Namespaces. This allows several Classes to share a common set of methods, and provides a degree of multiple inheritance.
To import methods from a Namespace NS, the Class Script must include a statement:
:Include NS
When the Class is fixed by the editor or by ⎕FIX, all the defined functions and operators in Namespace NS are included as methods in the Class. The functions and operators which are brought in as methods from the namespace NS are treated exactly as if the source of each function/operator had been included in the class script at the point of the :Include statement. For example, if a function contains :Signature or :Access statements, these will be taken into account. Note that such declarations have no effect on a function/operator which is in an ordinary namespace.
Dfns and dops in NS are also included in the Class but as Private members, because dfns and dops may not contain :Signature or :Access statements. Variables and Sub-namespaces in NS are not included.
Note that objects imported in this way are not actually copied, so there is no penalty incurred in using this feature. Additions, deletions and changes to the functions in NS are immediately reflected in the Class.
If there is a member in the Class with the same name as a function in NS, the Class member takes precedence and supersedes the function in NS.
Conversely, functions in NS will supersede members of the same name that are inherited from the Base Class, so the precedence is:
Class supersedes
Included Namespace, supersedes
Base Class
Any number of Namespaces may be included in a Class and the :Include statements may occur anywhere in the Class script. However, for the sake of readability, it is recommended that you have :Include statements at the top, given that any definitions in the script will supersede included functions and operators.
For information on copying classes that reference namespaces in this way, see