objective c - Possible to set multiple parent entities for Core Data NSManagedObject? -

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i have created following example core data nsmanagedobject subclasses:

pbcommentableobject : nsmanagedobject // allow comments on object @property (nonatomic, retain) nsset *pbcomments; // unordered set of pbcomment objects  pbcomment : pbcommentableobject // allow comments on comment @property (nonatomic, retain) pbcommentableobject *target;  pblist : pbcommentableobject // allow comments on list @property (nonatomic, retain) nsorderedset *pbordereditems; // ordered set of pblistableobject objects  pbstring : pblistableobject // allow strings added lists @property (nonatomic, retain) nsstring *pbtext;  pblistableobject : ???? // i'd both pblist , pbstring pblistableobjects @property (nonatomic, retain) pblist *pblist;

the problem having following behavior:

  • lists (pblist) can hold ordered list of strings (pbstring) or other lists (pblist).
  • allow comments (pbcomment) on lists (pblist) , other comments (pbcomment) not strings (pbstring)

is possible do? trying build core data model via visual interface in xcode; , while conceive of using categories, don't know how without xcode spitting out warning when fail define relationship via visual editor.

i think stretching idiom of inheritance. "listable" , "commentable" results in quite unreadable complexity.

the validation of allowing or disallowing comments, lists or have you, can modeled using (boolean) attributes , relationships. try think of concrete objects such "comment" or "string" , model lists attribute sets.


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