C++

Forum

 
I get an error when trying to get value from the class in another class.

Tima11 (14)
Hello. I get an error when trying to get value from another class which are also in one big class. Error: Type name is not allowed.
Here is the actual code:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
 
namespace vector2d
{
	class fvector
	{
	public:
		class pixelQuantity
		{
			float px_quantity = 0.0f;
			float px_quantity_x_cycle = 0.0f;
			float px_quantity_y_cycle = 0.0f;
		};
		class transform
		{
			class position
			{
				float x1 = 0.0f;
				float y1 = 0.0f;
				float x2 = 0.0f;
				float y2 = 0.0f;
				//Calculate X Center of a vector
				float centerx()
				{
					return (x2 - x1) / 2.0f;
				}
				//Calculate Y Center of a vector
				float centery()
				{
					return (y2 - y1) / 2.0f;
				}
			};
			class rotation
			{
				float angle = 0.0f;
				pivot pivot_rotation = center;
				rotation_direction_ rotation_direction = clockwise;
			};
			class size
			{
				int thickness_l = 1; //thickness left
				int thickness_r = 1; //thickness right
		                //Calculate Vector's magnitude
				float magnitude()
				{
					float adx = fabs(position.x2 - position.x1);
					float ady = fabs(position.y2 - position.y1);
					return sqrt(adx * adx + ady * ady);
				}
			};
		};

Error is in the magnitude() function and when i create an object vector2d::fvector v1() and try to access v1.transform i also get an error that Type name is not allowed.
Last edited on
seeplus (6591)
That is unreadable! Please post the actual code and the compiler provided errors.
keskiverto (10402)
IMHO, bitmap images are atrocious.

Do you really need nested class definitions?


You have:
1
2
3
4
5
6
7
8
9
 
class A {
  float x;
};

class B {
  float func() {
    return A.x; // error: type name not allowed
  }
};

That error is obvious. The A is a type, just like int. You can't write:
1
2
 
int = 3;
std::cout << (int + 39);

You have to write:
1
2
 
int y = 3;
std::cout << (y + 39);

Similarly,
1
2
3
 
A aaa;
A bbb;
A ccc[3];

The aaa, bbb, ccc[0], ccc[1], and ccc[2] are objects of type A. Each of these objects has member x.
You could write:
1
2
3
4
5
 
class B {
  float func(A y) {
    return y.x;
  }
};

Now there is instance y of A with concrete x.

That would still give an error, because x is a private member of type A, but that you can solve by improving the interface of A.
Tima11 (14)
Thanks keskiverto! I experimented with your solution to this problem and everything worked fine!
Topic archived. No new replies allowed.