Hi people,

I have a slight problem an having trouble to understand why it's causing a compile error.

error C2664: 'Lex::LinkedList<T>::setSortQuery' : cannot convert parameter 1 from 'Lex::LinkedList<T>::SortReturnCode (__cdecl *)(const Data,const Data)' to 'Lex::LinkedList<T>::SortReturnCode (__cdecl *)(const T,const T)'
with
[
T=Data *
]
None of the functions with this name in scope match the target type[/quote]

Here is a code snippet



template<class T>
class LinkedList
{
public:

enum SortReturnCode{LOWEST=1, HIGHEST=2, IDENTICAL=4};

typedef SortReturnCode (*SortQueryFncPtr)(const T Data1, const T Data2);

void setSortQuery(SortQueryFncPtr pSortQueryFncPtr)
{
m_pSortQueryFncPtr = pSortQueryFncPtr;
}

private:

SortQueryFncPtr m_pSortQueryFncPtr;
};

struct Data
{
char cTest[255];
};

static LinkedList<Data*>::SortReturnCode SortTest(const Data *Test1, const Data *Test2)
{
return LinkedList<Data*>::IDENTICAL;
}

int main()
{
LinkedList<Data*> listTest;

listTest.setSortQuery(SortTest);

return 0;
}

If I create a list container that contains a non-pointer value, (T=Data), then there is no error. Could anyone be kind to explain why I retrieve this error.

thanks

Hi,

Thanks for the reply, SiCrane, *high five*

That makes sense I guess, I just presumed that it would const binds to the pointed type as it works for referencing type.

So how would one go about making sure it would const binds to the pointed type? I'm guessing that I would change :


[color=#660066]SortQueryFncPtr[color=#666600])([color=#000088]const[color=#000000] T [color=#660066]Data1[color=#666600],[color=#000000] [color=#000088]const[color=#000000] T [color=#660066]Data2[color=#666600])

to


[color=#660066]SortQueryFncPtr[color=#666600])([color=#000088]const[color=#000000] T *[color=#660066]Data1[color=#666600],[color=#000000] [color=#000088]const[color=#000000] T *[color=#660066]Data2[color=#666600])
?

Thanks

Hi,

Duh, that's bad of me, I should really read more carefully rather than get frustrated lol.

Thanks for the reply, SiCrane, *high five*

Hi,

Ah that would do the trick, thanks very very much . Never came across this problem before nor have I read about it, learn something new everyday.

Thanks very much