The following code using Lambda with vector iterators compiles without complaint: vector<char> v; find_if(v.begin(), v.end(), _1 == 'x'); Ditto for this code, which uses istream_iterators: istream_iterator<char> b1(cin); istream_iterator<char> e1; find_if(b1, e1, _1 == 'x'); But the same code with istreambuf_iterators gets rejected: istreambuf_iterator<char> b2(cin); istreambuf_iterator<char> e2; find_if(b2, e2, _1 == 'x'); Error messages from VC8 and gcc 4.1.1 are below. Am I doing something wrong, is there a bug in Lambda regarding istreambuf_iterators, or is this a restriction that I didn't see documented somewhere? Thanks, Scott VC8 says: lambda.cpp D:\Apps\Microsoft Visual Studio 8\VC\INCLUDE\algorithm(87) : error C2664: 'bool boost::lambda::lambda_functor<T>::operator ()<char>( A &) const' : cannot convert parameter 1 from 'char' to 'char &' [Instantiation traceback omitted] gcc 4.1.1. says: stl_algo.h:188: error: no match for call to '( boost::lambda::lambda_functor< boost::lambda::lambda_functor_base< boost::lambda::relational_action<boost::lambda::equal_action> , boost::tuples::tuple< boost::lambda::lambda_functor< boost::lambda::placeholder<1> >, const char > > > ) (char)' stl_algo.h: In function 'istreambuf_iterator<char, char_traits<char> > __find_if( istreambuf_iterator<char, char_traits<char> > , istreambuf_iterator<char, char_traits<char> > , boost::lambda::lambda_functor< boost::lambda::lambda_functor_base< boost::lambda::relational_action<boost::lambda::equal_action> , boost::tuples::tuple< boost::lambda::lambda_functor< boost::lambda::placeholder<1> >, const char > > >, input_iterator_tag )': [Instantiation traceback omitted]