AMDG MuTPu4 wrote:

While using standart algorithm wrappers (::boost::lambda::ll) I find out that there is no way to call non-constant versions of begin/end without defining new helper functors in the user code. In other words, algorithms like ll::sort as- is are unusable. I think it would be nice to add a pair of non-const helper functors, i.e. call_mutable_begin and call_mutable_end to the library.

Perhaps deducing the iterator type from the constness of the parameter would be even better? template<class T> struct get_iterator { typedef typename T::iterator type; }; template<class T> struct get_const_iterator { typedef typename T::const_iterator type; }; struct call_begin { template<class Args> struct sig { typedef typename boost::tuples::element<1, Args>::type arg_type; typedef typename boost::mpl::eval_if<boost::is_const<arg_type>, get_const_iterator<arg_type>, get_iterator<arg_type> >::type type; }; template<class T> typename T::iterator operator()(T& t) const { return(t.begin()); } template<class T> typename T::const_iterator operator()(const T& t) const { return(t.begin()); } }; In Christ, Steven Watanabe