mem_fun and C2784 using Ms VC++

[Mr X]

Can anyone tell how to fix the compile error for the program below?

#include "iostream.h "
#include <vector>
#include <algorithm>
#include <functional>
#include <list>

using namespace std;

class Widget
{
};

class B
{
public:
bool IsInteresting(W idget) {return true;}
};

class C
{
public:
void Find(B b)
{
list<Widget>::i terator i = find_if(m_widge ts.begin(),m_wi dgets.end(),
mem_fun_ref((*t his).IsInterest ing));
}
private:
list<Widget>m_w idgets;
bool IsInteresting(c onst Widget widget) {return true;}
};

void main(void)
{};

[Victor Bazarov]

Mr X wrote:

Can anyone tell how to fix the compile error for the program below?

#include "iostream.h "'
Ugh!

#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <list>

using namespace std;

class Widget
{
};

class B
{
public:
bool IsInteresting(W idget) {return true;}
};

class C
{
public:
void Find(B b)
{
list<Widget>::i terator i = find_if(m_widge ts.begin(),m_wi dgets.end(),
mem_fun_ref((*t his).IsInterest ing));
Shouldn't this be

mem_fun_ref(&C: :IsInteresting)

?
}
private:
list<Widget>m_w idgets;
bool IsInteresting(c onst Widget widget) {return true;}
};

void main(void)
Yuck!
{};

Bleh!

[Mr X]

This doesn't work either: (can someone come up with something that
does?)

#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <list>

using namespace std;

class Widget
{};

class B
{};

class C
{
public:
void Find(B b)
{
Widget widget;
std::find_if(m_ widgets.begin() ,m_widgets.end( ),std::bind2nd( std::mem_fun(&C ::IsInteresting ),widget));
}
private:
bool IsInteresting(W idget) {return true;}
list<Widget>m_w idgets;
};

[Victor Bazarov]

Mr X wrote:

This doesn't work either: (can someone come up with something that
does?)

#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <list>

using namespace std;

class Widget
{};

class B
{};

class C
{
public:
void Find(B b)
{
Widget widget;
std::find_if(m_ widgets.begin() ,m_widgets.end( ),std::bind2nd( std::mem_fun(&C ::IsInteresting ),widget));
Not sure what you're trying to accomplish, but this:

std::find_if(m_ widgets.begin() ,
m_widgets.end() ,
std::bind1st(st d::mem_fun(&C:: IsInteresting), this));

should at least compile.
}
private:
bool IsInteresting(W idget) {return true;}
list<Widget>m_w idgets;
};

V

[Mr X]

It doesn't :
error C2784: 'class std::mem_fun_t< _R,_Ty> __cdecl std::mem_fun(_R
(__thiscall _Ty::*)(void))' : could not deduce template argument for
'<Unknown>
' from 'bool (__thiscall C::*)(class Widget)'

[Victor Bazarov]

Mr X wrote:

It doesn't :
error C2784: 'class std::mem_fun_t< _R,_Ty> __cdecl std::mem_fun(_R
(__thiscall _Ty::*)(void))' : could not deduce template argument for
'<Unknown>
' from 'bool (__thiscall C::*)(class Widget)'

Get a better compiler.

[puzzlecracker]

Can someone explain bind2st/bind1st stl functions?
thx

[Victor Bazarov]

"puzzlecrac ker" <ir*********@gm ail.com> wrote...

Can someone explain bind2st/bind1st stl functions?

What to explain? "Use the Source, Luke!" -- just look at the
'functional' header and find the source for those functions. They
are _literally_ one-liners.

Besides, what book on templates are you reading that doesn't talk
about bind1st/2nd?

[puzzlecracker]

dont remember those !

[Mike Wahler]

"Victor Bazarov" <v.********@com Acast.net> wrote in message
news:KH******** ***********@new sread1.mlpsca01 .us.to.verio.ne t...

Mr X wrote:

It doesn't :
error C2784: 'class std::mem_fun_t< _R,_Ty> __cdecl std::mem_fun(_R
(__thiscall _Ty::*)(void))' : could not deduce template argument for
'<Unknown>
' from 'bool (__thiscall C::*)(class Widget)'

Get a better compiler.

Yes. VC++ (at least versions 6.0 and earlier)
is notorious for weak template support.

-Mike