Re: [Boost-users] [bind] [lambda] making lambda::bind work

From: Peter Dimov (pdimov_at_[hidden])
Date: 2008-09-01 13:13:19

Peter Barker:

> void LambdaBind()
> {
> std::auto_ptr<GridItem> item(new GridItem());
> std::vector<std::string> options;
>
> using namespace boost::lambda;
> using boost::lambda::_1;
> std::for_each(options.begin(),options.end(),
> 
> bind(GridItem::AddOption,boost::ref(item),bind(std::string::c_str,_1),true));
> // COMPILE ERROR ON ABOVE
> }
>
> int main()
> {
> }
>
> The error is:
> c:\releases\lib\boost\boost_1_35_0\include\boost\bind.hpp(338) : error 
> C2664: 'R boost::_mfi::mf2<R,T,A1,A2>::operator 
> ()<std::auto_ptr<_Ty>>(const U &,A1,A2) const' : cannot convert parameter 
> 2 from 'boost::lambda::lambda_functor<T>' to 'const char *'

Since you use an unqualified call to bind, argument-dependent lookup finds 
boost::bind and prefers it as a better match. Nasty.

You need '&' in front of the member functions, by the way. Omitting it is a 
MSVC-ism.