eieio: eieio-instance-inheritor
12.1 ‘eieio-instance-inheritor’
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This class is defined in the package ‘eieio-base’.
Instance inheritance is a mechanism whereby the value of a slot in
object instance can reference the parent instance. If the parent’s slot
value is changed, then the child instance is also changed. If the
child’s slot is set, then the parent’s slot is not modified.
-- Class: eieio-instance-inheritor parent-instance
A class whose instances are enabled with instance inheritance. The
PARENT-INSTANCE slot indicates the instance which is considered the
parent of the current instance. Default is ‘nil’.
To use this class, inherit from it with your own class. To make a
new instance that inherits from and existing instance of your class, use
the ‘clone’ method with additional parameters to specify local values.
The ‘eieio-instance-inheritor’ class works by causing cloned objects
to have all slots unbound. This class’ ‘slot-unbound’ method will cause
references to unbound slots to be redirected to the parent instance. If
the parent slot is also unbound, then ‘slot-unbound’ will signal an
error named ‘slot-unbound’.
Info Catalog
eieio: Base Classes
eieio: eieio-instance-tracker