Combining Proto and Parent Inheritance
_parent
pointer much as you could directly use the _proto
pointer. But it does not work as you intend. Instead, you'll usually use :Parent()
, a view message that returns the parent view. If you happen to be writing methods for nonview objects, you can use self._parent
.For example, instead of:
Print("my parent is" && _parent);use:
Print("my parent is" && :Parent());
_parent
because of a quirk in the current NewtonScript runtime implementation. The runtime interpreter itself uses inheritance. As your method is executing, _parent
and self
both point to the frame that received the message. Only when you use self._parent
will you retrieve the _parent
slot from the correct frame.
An online version of Programming for the Newton using Macintosh, 2nd ed. ©1996, 1994, Julie McKeehan and Neil Rhodes.
Last modified: 1 DEC 1996