Some results on running 'g++ -E | wc -l' with the appropriate includes/defines and a single #include in a compilation unit: boost/signal.hpp : 62141 boost/signals/trackable.hpp : 40849 boost/tokenizer.hpp : 39490 boost/iterator/indirect_iterator : 36922 boost/signals/connection.hpp : 34957 boost/function.hpp : 31379 boost/array.hpp : 30205 boost/utility.hpp : 30063 boost/cregex.hpp : 21575 boost/shared_ptr.hpp : 17469 boost/scoped_ptr.hpp : 11411 boost/crc.hpp : 5851 boost/tuple/tuple.hpp : 4927 boost/scoped_array.hpp : 3029 boost/assert.hpp : 52 boost/current_function.hpp : 21 string : 18781 vector : 11994 map : 12467 list : 11134 deque : 11805 iosfwd : 6462 iostream : 29529 QObject : 5601 QString : 3876 QList : 1931 QVector : 4165 QMap : 2831 QHash : 7098 QRegExp : 3959 (boost/cregex.hpp : 21575 QSharedData : 838 (boost/shared_ptr.hpp : 17469)