Re: [boost] token_iterator flaw, format and date_time shadowing, regex gcc.mak problem, and Boost.Format suggestion

From: Stephan T. Lavavej (stl_at_[hidden])
Date: 2005-07-27 22:10:07

[STL]
> I have noted the following about Boost 1.32.0.
> 1. boost/token_iterator.hpp is very broken on line 34.
> 
>   template <class TokenizerFunc, class Iterator, class Type>
>   class token_iterator
>       : public iterator_facade<
>             token_iterator<TokenizerFunc, Iterator, Type>
>           , Type // ********** SHOULD READ: const Type
>           , typename detail::minimum_category<
>                 forward_traversal_tag
>               , typename iterator_traversal<Iterator>::type
>             >::type
>           , const Type&
>         >
> 
> GCC 3.4.2 refuses to compile this when broken.

[Dave Abrahams]
> Why do you think so? 

I'm sorry, I misremembered it as a hard error.  Actually, it produces a
nontrivial warning under -Wcast-qual:

C:/MinGW/bin/../lib/gcc/i686-pc-mingw32/3.4.2/../../../../include/boost/iter
ator/iterator_facade.hpp: In static member f
unction `static typename boost::mpl::if_<boost::is_reference<Reference>,
Pointer, boost::detail::operator_arrow_proxy<Va
lueType> >::type boost::detail::operator_arrow_result<ValueType, Reference,
Pointer>::make(Reference) [with ValueType =
std::basic_string<char, std::char_traits<char>, std::allocator<char> >,
Reference = const std::basic_string<char, std::c
har_traits<char>, std::allocator<char> >&, Pointer = std::basic_string<char,
std::char_traits<char>, std::allocator<char
> >*]':
C:/MinGW/bin/../lib/gcc/i686-pc-mingw32/3.4.2/../../../../include/boost/iter
ator/iterator_facade.hpp:644:   instantiated
 from `typename boost::detail::operator_arrow_result<typename
boost::detail::iterator_facade_types<Value, CategoryOrTrav
ersal, Reference, Difference>::value_type, Reference, typename
boost::detail::iterator_facade_types<Value, CategoryOrTra
versal, Reference, Difference>::pointer>::type boost::iterator_facade<I, V,
TC, R, D>::operator->() const [with Derived
= boost::token_iterator<boost::char_separator<char, std::char_traits<char>
>, __gnu_cxx::__normal_iterator<const char*,
std::basic_string<char, std::char_traits<char>, std::allocator<char> > >,
std::basic_string<char, std::char_traits<char>
, std::allocator<char> > >, Value = std::basic_string<char,
std::char_traits<char>, std::allocator<char> >, CategoryOrTr
aversal = boost::forward_traversal_tag, Reference = const
std::basic_string<char, std::char_traits<char>, std::allocator
<char> >&, Difference = ptrdiff_t]'
C:/MinGW/bin/../lib/gcc/i686-pc-mingw32/3.4.2/../../../../include/boost/date
_time/time_parsing.hpp:81:   instantiated fr
om `time_duration boost::date_time::parse_delimited_time_duration(const
std::string&) [with time_duration = boost::posix
_time::time_duration]'
C:/MinGW/bin/../lib/gcc/i686-pc-mingw32/3.4.2/../../../../include/boost/date
_time/posix_time/time_parsers.hpp:27:   inst
antiated from here
C:/MinGW/bin/../lib/gcc/i686-pc-mingw32/3.4.2/../../../../include/boost/iter
ator/iterator_facade.hpp:325: warning: cast
from `const std::basic_string<char, std::char_traits<char>,
std::allocator<char> >*' to `std::basic_string<char, std::ch
ar_traits<char>, std::allocator<char> >*' discards qualifiers from pointer
target type

Stephan T. Lavavej