In Case Study 2, near the end it says "if the client may need to know SIDE_LENGTH, then you can add a function to return the value" Which yeah, you can do that

In Case Study 2, near the end it says "if the client may need to know SIDE_LENGTH, then you can add a function to return the value" Which yeah, you can do that but it's a constant so you can also more literally write (in the implementation just like that function): pub const SIDE_LENGTH: usize = ROW_LENGTH;