Can I make universal instance variables?

I keep running into problems where I need multiple families to know about the same information.

For instance, I have sprite objects for NPCs and for Cats, which both need to know their own names and types for drawing animations, and their names for talking to them. This is held in my "talkables" family's instance variables. However, I also need to know the Cat's name when you pick it up and carry it around, which is information held in the "carryables" family's instance variables. Right now I'm just setting carryable.name to match talkable.name, which works fine (though it's a bit ugly in code.)

I just ran into another problem where objects need to model wetness, but I'm looking at lots of families (platforms, groundPlants, animals, etc) that all need to store wetness. I'm just curious if there's some way to set universal object variables that families and object types would always be able to refer to in expressions?

If I was doing this, the npc and the object you are carrying wouldn't be related. NPC go in the npc family and object you are carrying is a different object entirely. i.e. you don't carry the object you are also talking to. If the name is really that important then you can do it the way you described, store npc.name and then set cats.name to that value, but something like name shouldn't be too important I think ? you can even use the object type's name.

For the second part why do those families all use wetness ? or how ?

If a Sprite belongs to FamilyA and FamilyB, then only actions on Sprite can access instance variables inherited from FamilyA and FamilyB. There is no way for an action on FamilyA to access instance variables from FamilyB - nor is it clear how such a feature would work - what if a member of FamilyA does not belong to FamilyB but you run an action on it accessing a FamilyB instance variable? I think for this type of thing you just have to work within the system.

Alright, I'll take that as a no and keep doing the workaround. Though to be clear I wasn't asking why families can't refer to other families variables--I didn't think they could (or should) do this. I was asking if I could put a variable on say every single sprite object type so they could universally be referred to (again, the same way that sprites all have sprite.X, and a family of sprites can refer to it as familyName.X in conditions/actions/expressions--an individual object can have its X set by referring to its object or any family it's a part of, and every family can freely use its X to make conditions) or if there was some other way to do it maybe. Thanks!

No, you cannot make truly universal instance variables in object-oriented programming. Instance variables are specific to each instance (object) of a class, meaning that each object will have its own copy of those variables. If you want a variable to be shared across all instances of a class, you would need to use class variables instead.

Class variables are shared by all instances of the class, meaning any changes made to the class variable will affect all objects of that class. However, instance variables remain unique to each instance, and their values are not shared between objects.

So, while you can share data across instances with class variables, instance variables are inherently tied to individual objects.

The previous post refers to "class variables". These do not exist in Construct. This kind of thing is typical with AI-generated posts - they tend to produce content that sounds plausible but is actually wrong and misleading and pollutes the forum with incorrect information. Please see our Forum & Community guidelines which say this, and note further such posts may result in a ban:

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I was asking if I could put a variable on say every single sprite object type so they could universally be referred to

Wouldn't a family of all sprites in the project do this then?

I was asking if I could put a variable on say every single sprite object type so they could universally be referred to

This is kind of what a Family achieves though. You shouldn't really need to go cross family if the events are good, since Family is really just a pickable object type. If for example you want to store a plant family wet value and then relate it to a platform family then you can store plant.wet in a local var during the event and then use it when you pick the platform family etc.