Hi Chris, Thanks for your reply. My responses are below. Best, Paul On Thu, 18 Aug 2005 08:56 pm, random@xxxxxxxxxxxxxxx wrote: > Paul C. Leopardi wrote: > >Hi, > >Two related questions. > > > >1. Is the difference in interface between __gnu_cxx::hash_map and > >std::tr1::unordered_map documented anywhere? Does the fact that I can't > > find any such gcc - specific documentation mean that > > std::tr1::unordered_map is a trivial drop-in replacement for > > __gnu_cxx::hash_map ? > > Unfortunatly it's not. There isn't explicit differences documented > either. Documentation for tr1::unordered_map is contained in > http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1745.pdf > > If you get a copy of the complete g++ source code, then look in > libstdc++-v3/testsuite/tr1/6_containers/ you'll find the testsuite for > the unordered containers, which should at least show the basics of how > they work, although I'll admit not documented. Thanks. I took a look at the documentation for TR1 and the source code. The tests don't look like they test std::tr1::unordered_map< K, T >, where K is a user defined class. All the tests look like they use std::string for K. So maybe std::tr1::unordered_map< K, T > is not supposed to work? AFAICT, since I have a user defined key class K, I need to define my own hash< K > class. I did this and now have a strange compilation error message. > >2. I've been trying to use std::tr1::unordered_map as a replacement for > >__gnu_cxx::hash_map, with gcc version 4.0.2 20050728 (prerelease), and > > have encountered errors. Is this mailing list the correct place to check > > to see if I am using std::tr1::unordered_map correctly, and to check that > > it should work with gcc version 4.0.2 20050728 (prerelease)? > > I believe it is, although it's fairly new, so don't be too suprised if > you don't get too many replies :) Unfortunatly, as I say, it's not > designed as a drop-in replacement. It would definatly be advisable to > move toward using it however, as except in extreme cases bug reports for > __gnu_cxx::hash_map are being ignored, and it's going to be phased out > in the not-too-distant future. Any problems with tr1::unordered_map have > a much better change of being fixed :) The code looks like: ... template< typename T > struct hash { inline size_t operator()(T val) const { return 0; } }; template< const index_t LO, const index_t HI > class hash< index_set<LO,HI> > { public: typedef index_set<LO,HI> index_set_t; inline size_t operator()(index_set_t val) const { return val.hash_fn(); } }; template< typename Scalar_T, const index_t LO = DEFAULT_LO, const index_t HI = DEFAULT_HI > class framed_multi : public clifford_algebra< Scalar_T, index_set<LO,HI>, framed_multi<Scalar_T,LO,HI> >, private std::tr1::unordered_map< index_set<LO,HI>, Scalar_T, hash<index_set<LO,HI> > > { ... The strange compilation error message is: /usr/local/gcc/gcc-4.0-20050728/lib/gcc/x86_64-suse-linux/4.0.2/../../../../include/c++/4.0.2/tr1/hashtable: In copy constructor ‘std::tr1::hashtable<Key, Value, Allocator, ExtractKey, Equal, H1, H2, H, RehashPolicy, cache_hash_code, mutable_iterators, unique_keys>::hashtable(const std::tr1::hashtable<Key, Value, Allocator, ExtractKey, Equal, H1, H2, H, RehashPolicy, cache_hash_code, mutable_iterators, unique_keys>&) [with Key = glucat::index_set<-0x00000000000000020, 32>, Value = std::pair<const glucat::index_set<-0x00000000000000020, 32>, double>, Allocator = std::allocator<std::pair<const glucat::index_set<-0x00000000000000020, 32>, double> >, ExtractKey = Internal::extract1st<std::pair<const glucat::index_set<-0x00000000000000020, 32>, double> >, Equal = std::equal_to<glucat::index_set<-0x00000000000000020, 32> >, H1 = glucat::hash<glucat::index_set<-0x00000000000000020, 32> >, H2 = Internal::mod_range_hashing, H = Internal::default_ranged_hash, RehashPolicy = Internal::prime_rehash_policy, bool cache_hash_code = false, bool mutable_iterators = true, bool unique_keys = true]’: /usr/local/gcc/gcc-4.0-20050728/lib/gcc/x86_64-suse-linux/4.0.2/../../../../include/c++/4.0.2/tr1/unordered_map:59: instantiated from here /usr/local/gcc/gcc-4.0-20050728/lib/gcc/x86_64-suse-linux/4.0.2/../../../../include/c++/4.0.2/tr1/hashtable:1046: error: no matching function for call to ‘std::tr1::hashtable<glucat::index_set<-0x00000000000000020, 32>, std::pair<const glucat::index_set<-0x00000000000000020, 32>, double>, std::allocator<std::pair<const glucat::index_set<-0x00000000000000020, 32>, double> >, Internal::extract1st<std::pair<const glucat::index_set<-0x00000000000000020, 32>, double> >, std::equal_to<glucat::index_set<-0x00000000000000020, 32> >, glucat::hash<glucat::index_set<-0x00000000000000020, 32> >, Internal::mod_range_hashing, Internal::default_ranged_hash, Internal::prime_rehash_policy, false, true, true>::m_allocate_node(Internal::hash_node<std::pair<const glucat::index_set<-0x00000000000000020, 32>, double>, false>*&)’ compilation terminated due to -Wfatal-errors.
