Re: [Boost-users] [bind] Member fn has defeated me

From: BRIDGES Dick (Dick.Bridges_at_[hidden])
Date: 2005-10-05 11:59:11

> -----Original Message-----
> From: boost-users-bounces_at_[hidden] 
> [mailto:boost-users-bounces_at_[hidden]] On Behalf Of Peter Dimov
> Sent: Tuesday, October 04, 2005 3:49 PM
> To: boost-users_at_[hidden]
> Subject: Re: [Boost-users] [bind] Member fn has defeated me
> 
> 
> BRIDGES Dick wrote:
> 
> > class Bar {
> >  typedef void (*pf)(bool);
> 
> If you make this
> 
>     typedef boost::function<void(bool)> pf;
> 
[snip]
> 
> then
> 
>   Bar bar_( boost::bind(&X::f, &x) );
> 
> should work. But you can't get an oridnary function pointer from 
> boost::bind; a function pointer doesn't have enough state to 
> represent &X::f 
> + &x. 

<error_message>

Building file: ../main.cpp
g++ -D_REENTRANT -I/boost_1_33_0 -O0 -g3 -Wall -c -
fmessage-length=0 -omain.o ../main.cpp
/boost_1_33_0/boost/bind.hpp: In instantiation of 
?boost::_bi::result_traits<boost::_bi::unspecified, void 
(X::*)(bool)>?:
/boost_1_33_0/boost/bind/bind_template.hpp:15:   
instantiated from 
?boost::_bi::bind_t<boost::_bi::unspecified, void 
(X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> > >?
../main.cpp:197:   instantiated from here
/boost_1_33_0/boost/bind.hpp:63: error: ?void (X::*)(bool)? 
is not a class, struct, or union type
/boost_1_33_0/boost/bind/bind_template.hpp: In 
instantiation of 
?boost::_bi::bind_t<boost::_bi::unspecified, void 
(X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> > >?:
../main.cpp:197:   instantiated from here
/boost_1_33_0/boost/bind/bind_template.hpp:15: error: no 
type named ?type? in ?struct 
boost::_bi::result_traits<boost::_bi::unspecified, void 
(X::*)(bool)>?
...
[previous line repeated 23 times - increasing __LINE__]
...
/boost_1_33_0/boost/function/function_template.hpp: In 
static member function ?static void 
boost::detail::function::void_function_obj_invoker1<Functio
nObj, R, T0>::invoke(boost::detail::function::any_pointer, 
T0) [with FunctionObj = 
boost::_bi::bind_t<boost::_bi::unspecified, void 
(X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> > >, 
R = void, T0 = bool]?:
/boost_1_33_0/boost/function/function_template.hpp:479:   
instantiated from ?void boost::function1<R, T0, 
Allocator>::assign_to(FunctionObj, 
boost::detail::function::function_obj_tag) [with 
FunctionObj = boost::_bi::bind_t<boost::_bi::unspecified, 
void (X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> 
> >, R = void, T0 = bool, Allocator = 
std::allocator<void>]?
/boost_1_33_0/boost/function/function_template.hpp:430:   
instantiated from ?void boost::function1<R, T0, 
Allocator>::assign_to(Functor) [with Functor = 
boost::_bi::bind_t<boost::_bi::unspecified, void 
(X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> > >, 
R = void, T0 = bool, Allocator = std::allocator<void>]?
/boost_1_33_0/boost/function/function_template.hpp:294:   
instantiated from ?boost::function1<R, T0, 
Allocator>::function1(Functor, typename boost::enable_if_c< 
boost::type_traits::ice_not< 
boost::is_integral<Functor>::value>::value, int>::type) 
[with Functor = boost::_bi::bind_t<boost::_bi::unspecified, 
void (X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> 
> >, R = void, T0 = bool, Allocator = 
std::allocator<void>]?
/boost_1_33_0/boost/function/function_template.hpp:638:   
instantiated from ?boost::function<R ()(T0), 
Allocator>::function(Functor, typename boost::enable_if_c< 
boost::type_traits::ice_not< 
boost::is_integral<Functor>::value>::value, int>::type) 
[with Functor = boost::_bi::bind_t<boost::_bi::unspecified, 
void (X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> 
> >, R = void, T0 = bool, Allocator = 
std::allocator<void>]?
../main.cpp:197:   instantiated from here
/boost_1_33_0/boost/function/function_template.hpp:136: 
error: no match for call to 
?(boost::_bi::bind_t<boost::_bi::unspecified, void 
(X::*)(bool), boost::_bi::list1<boost::_bi::value<X*> > >) 
(bool&)?
make: *** [main.o] Error 1
</error_message>

Peter,

Your suggestion sure made sense.  I clearly did something wrong
but can't figure out what that would be.  I must be interpreting
the error message incorrectly.  I interpret it to say that the
compiler can't find the definition of X but

  X x;
  x.f(true);

compiles without any problem.  Where should I be looking?

Regards,
Dick