Help: chparents()

Showing help on 'chparents()'

Syntax: chparent (OBJ object, OBJ new-parent) => NONE
chparents (OBJ object, LIST new-parents) => NONE

chparent -- Changes the parent of object to be new-parent.
chparents -- Changes the parent of object to be new-parents.

If object is not valid, or if new-parent is neither valid nor equal to #-1, then E_INVARG is raised. If the programmer is neither a wizard or the owner of object, or if new-parent is not fertile (i.e., its f bit is not set) and the programmer is neither the owner of new-parent nor a wizard, then E_PERM is raised. If new-parent is equal to object or one of its current ancestors, E_RECMOVE is raised. If object or one of its descendants defines a property with the same name as one defined either on new-parent or on one of its ancestors, then E_INVARG is raised.

Changing an object's parent can have the effect of removing some properties from and adding some other properties to that object and all of its descendants (i.e., its children and its children's children, etc.). Let common be the nearest ancestor that object and new-parent have in common before the parent of object is changed. Then all properties defined by ancestors of object under common (that is, those ancestors of object that are in turn descendants of common) are removed from object and all of its descendants. All properties defined by new-parent or its ancestors under common are added to object and all of its descendants. As with create(), the newly-added properties are given the same permission bits as they have on new-parent, the owner of each added property is either the owner of the object it's added to (if the c permissions bit is set) or the owner of that property on new-parent, and the value of each added property is clear; see the description of the built-in function clear_property() for details. All properties that are not removed or added in the reparenting process are completely unchanged.

If new-parent is equal to #-1, then object is given no parent at all; it becomes a new root of the parent/child hierarchy. In this case, all formerly inherited properties on object are simply removed.

If new-parents is equal to {}, then object is given no parent at all; it becomes a new root of the parent/child hierarchy. In this case, all formerly inherited properties on object are simply removed.

Warning: On the subject of multiple inheritance, the author (Slither) thinks you should completely avoid it. Prefer composition over inheritance.