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X-Hacker.org- Class(y) - <b>external methods</b>
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External Methods
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An external method is a method which is defined in a different module
from the one in which its class declaration appears.
This could be done for a number of reasons:
. To have a single method which applies to a number of different
classes. In most cases, however, such methods would be better
implemented in a parent class from which all classes requiring that
method are inherited, directly or indirectly.
. To implement a method in a C or assembler module.
. To prevent a method from being linked in automatically. This is
not a recommended practice. See the section Linking of classes.
External methods should be declared in the class which they belong
using the MESSAGE...METHOD command.
They should be defined (using the METHOD FUNCTION or METHOD PROCEDURE
commands) in a separate module which does not contain a class
declaration. Since such methods then automatically have public scope,
they should be given names that will not conflict with any other names
in the application. To cause an external method to be linked into an
application, you must include a Clipper EXTERNAL declaration with the
name of the method either in the module containing that method's class
declaration, or in the module which invokes the method.
See Also: MESSAGE...METHOD METHOD [FUNCTION] Linking of Classes
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