On Wed, Dec 10, 2008 at 2:37 PM, Frank Mori Hess <frank.hess@nist.gov>wrote: Thanks for that Frank - that just shows the perils of not posting the exact code which is causing problems! I have fabricated a much shorter example which exhibits the same issue for me... #include <cstddef> #include "boost/lambda/lambda.hpp" #include "boost/lambda/bind.hpp" #include "boost/function.hpp" template < typename T > bool is_zero( const T & t ) { return t == 0; } template < typename T, std :: size_t sz > bool first_element_equal_zero( const T ( & array )[ sz ] ) { using namespace boost; using lambda :: bind; using lambda :: _1; using lambda :: constant_ref; function< const T &( unsigned ) > element = constant_ref( array )[ _1 ]; function< bool( unsigned ) > e = bind( is_zero< T >, element( _1 ) ); return e( 0 ); } int main( ) { int a[ 10 ]; first_element_equal_zero( a ); } $ g++ -c element.cpp element.cpp: In function `bool first_element_equal_zero(const T (&)[sz]) [with T = int, unsigned int sz = 10u]': element.cpp:30: instantiated from here element.cpp:21: error: no match for call to `(boost::function<const int&()(unsigned int)>) (const boost::lambda::lambda_ functor<boost::lambda::placeholder<1> >&)' /usr/include/boost/function/function_template.hpp:810: note: candidates are: typename boost::function1<R, T0>::result_ty pe boost::function1<R, T0>::operator()(T0) const [with R = const int&, T0 = unsigned int] Which still evades my comprehension! I'd appreciate some guidance here. Thanks. - Rob.