Re: [Boost-users] Simply including boost/bind.hpp causes compilation error

From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-05-10 12:12:08

AMDG

Ken Smith wrote:
> Here is the code.
>
>   1 #include <boost/lambda/lambda.hpp>
>   2 #include <boost/lambda/construct.hpp>
>   3 #if defined(INCLUDE_BOOST_BIND)
>   4 #   include <boost/bind.hpp>
>   5 #endif
>   6 #include <iostream>
>   7 #include <iterator>
>   8 #include <algorithm>
>  30
>  31 int main()
>  32 {
>  33     using namespace std;
>  34     using namespace boost::lambda;
>  35
>  36     typedef std::istream_iterator<int> in;
>  37     std::for_each(in(std::cin), in(), std::cout << (_1 * 3) << " " );
>  76 }
>
> Any ideas?
>   

Boost.Bind declares the placeholders _1, _2, etc at global scope.
Boost.Lambda declares the placeholders _1, _2, and _3 in namespace 
boost::lambda.
The use of _1 in this context is ambiguous.  Try qualifying it.
namespace bll = boost::lambda;

(bll::_1 * 3)

In Christ,
Steven Watanabe