What does "generate const class"?

Development Programming & Scripting
1

Simple question, searching for this keyword “const” give me many page about “construction” so i cant find information about this, what does the checkbox “generate const class” do in the class setting panel?

2

I’m also trying to figure out what this is. If you have found out, could you please explain or lead me to right direction? :slight_smile:

3

haha, i asked this the 27 october 2015 and i still dont know what it does :o

good luck for your search, take the direction you want :slight_smile:

4

I believe that in this context it is the same as declaring something “const” as in C and C++. I’m going to assume here, that it means the class have unchanging values. Perhaps this Wikipedia Article on the subject may help.

Const (Computer Programming)

5

What I understood from Const Functions in C++, if we check that box, we won’t be able to change any variables of the blueprint in realtime?! I’ll give it a try and reply back.

Thanks.

6

lol thanks :slight_smile:

7

All properties and functions in this class are const and should be exported as const. This flag is inherited by subclasses.

Unreal Engine 4.9 Documentation

1 Like
8

Its related with pure c++ knowledge.

Construction are not related with const.

Const means your intention is not to change anything.
If its marking variable → You dont want to change variable.

int x = 5;
x = 6; // you can do this

const int y = 10;
y = 15; // ERROR: You marked it with const.

If its marking function → You dont want to change member anything in the class inside of function.

class SomeClass
{
public:
  SomeClass(); // EXTRA answer : This is CONSTRUCTOR which is not related with const.

  void DoSomething()
  {
      a = 15; // You can do it.
  }

  void DoSomethingElse() const
  {
     a = 15; // ERROR : Nope you cant do it. Because you marked function with const.
  }


private:
  int a = 10;
}

If its marking class -> You dont want to change anything in class. But its not logical in c++ terminology.

Constructor on the other hand something you can use to construct your object, which you can see the example above. There are different types and implementations of it. Which I dont need to dive into that topic here.

9

From the documentation when a class is marked as const (short for constant)

“All properties and functions in this class are const and are exported as const. This Specifier is inherited by subclasses.”