> namespace Filter{
>
> class ResultType {...};
> class SubExpression
> {
> public:
>   virtual ResultType Result()=0;
> };
> typedef boost::shared_ptr<SubExpression> SPtrSubExpression;
> ............
> void F()
> {
>    namespace la=boost::lambda;
>    ResultType r;
>    vector<SPtrSubExpression> v;
> ..................................
>    vector<SPtrSubExpression>::const_iterator i=find_if(v.begin(), v.end(),
>         la::bind(&SubExpression::Result, *la::_1)==r);
> }
>
> }
>

> c:\Program Files\boost-1-32-0\boost\tuple\detail\tuple_basic.hpp(419): error C2259: 'Filter::SubExpression' : cannot instantiate abstract class