Can not understand why compiler don't detect an error;

[derivarol]

Hi)
Can someone help me with one problem?)
In my project there are two files: cT.h (file header of some class cT) and main.cpp; The code of these files shown below;

cT.h

class cT
{
public:
cT();
~cT();
};

main.cpp

#include "cT.h"

int main()
{

cT *_a; //Why compiler tell that everything is OK? But we don't have a realization of constructor and destructor!

return 0;
}

In my opinion the compiler must tell that it can not find the realization of cT() and ~cT(); Please, explain me this.

[Athar]

That is because you just have a pointer to cT, not an actual instance of cT.
Neither the constructor nor the destructor is ever called, so the linker has no reason to complain.

[derivarol]

Sorry...

[wtf]

sorry my bad, but wouldn't it be ok anyway? I mean its not like the constructor is private or anything??? sorry I'm new don't fully understand instances of classes yet and all that jazz...

[wtf]

never mind I got it now its because he only declared the constructor etc yet not defined them?
I usually declare & define my constructors in the header file so I didn't notice.