I want to optimise my game code.
.ClassName == “Class” is faster than :IsA(“Class”)
Assume we run some search function you know?
Which is faster? It think .ClassName is faster because it’s a hash
Doesn’t really matter tbh, they just do the same thing. But I find :IsA() to be more readable, but I’m not sure if it’s faster, but the difference is probably minimal. I also see it more often than ClassName.
So you do you ig.
What’s the difference anyway?
Object:IsA and Instance.ClassName do have distinct differences. It has to do with class hierarchies. Roblox is based on the OOP (object-oriented programming) paradigm, which is where classes are derived from. A class is simply a unique blueprint that describes some sort of object.
Objects can be based on other objects, which is how hierarchies are born. For example, Instance defines the root behaviour of virtually every object in Roblox. Then take a Model, for example. The Model is an extension of the Instance class with additional functions and features. We call this extension a subclass, which in turn makes Instance its superclass.
The key difference between Object:IsA and Instance.ClassName is that Instance.ClassName states the immediate class of the object, while Instance:IsA can be used to ask if it is either an exact class or a subclass of one.
Being able to ask more open-ended questions about an instance’s class is useful. For example, say you wanted to detect if a given value is any kind of Part. The problem is, there’s MeshPart’s, UnionOperations etc, all of which you’d have to account for in your if-statement. Instead of brute-forcing all the possible part-like classes, we can ask a single question, which is if the given part is a descendant of the BasePart class. This will automatically account for all part types:
if part:IsA("BasePart") then
So, which one?
Typically, Object:IsA is reserved for questions like these. If you’re looking for an exact class, it’s better to match the class with Instance.ClassName. The latter is technically faster due to it being a direct comparison over a hierarchy check, which requires more operations
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.ClassName is probably faster because it doesn’t check if the target class inherits from the given class unlike :IsA which does check for inheritance.
I haven’t tested it, nor checked if the difference is negligible, so idk.