Question

My problem is that in my ‘Widget’ class i’ve the following declaration:

MouseEvent* X; 

In a member function I initialize the pointer with an address the normal way:

X = new MouseEvent; 

Ok, this last line makes the compiler stop at:

error C2166: l-value specifies const object

All right, a MouseEvent is declared as a typedef to simplify things:

typedef Event__2<void, Widget&, const MouseEventArgs&> MouseEvent; 

And Event__2 is, as you may imagine as: (basic structure shown):

template <typename return_type, typename arg1_T, typename arg2_T> class Event__2 {      ... }; 

I don’t know where the Event__2 class gets the const qualifier. Any tips ?

Thanks.

Answer 1

Likely, the member function where you are initializing X is marked as const – something like this.

class Foo {    int *Bar;  public:     void AssignAndDoStuff() const    {       Bar = new int; // Can't assign to a const object.       // other code    } } 

The solution here is either to

1. Assign to Bar in a separate non-const method,
2. change AssignAndDoStuff to be non-const, or
3. mark Bar as mutable.

Pick one of the above:

class Foo {    mutable int *Bar; // 3  public:    void Assign() // 1    {        Bar = new int;     }       void DoStuff() const    {        // Other code    }     void AssignAndDoStuff() // 2    {       Bar = new int;        // other code    } }