inline sequence<BidiIter> make_charset_xpression
(
compound_charset<Traits> &chset
, Traits const &tr
, regex_constants::syntax_option_type flags
)
{
typedef typename Traits::char_type char_type;
bool const icase = (0 != (regex_constants::icase_ & flags));
bool const optimize = is_narrow_char<char_type>::value && 0 != (regex_constants::optimize & flags);
// don't care about compile speed -- fold eveything into a bitset<256>
if(optimize)
{
typedef basic_chset<char_type> charset_type;
charset_type charset(chset.base());
if(icase)
{
charset_matcher<Traits, mpl::true_, charset_type> matcher(charset);
merge_charset(matcher.charset_, chset, tr);
return make_dynamic<BidiIter>(matcher);
}
else
{
charset_matcher<Traits, mpl::false_, charset_type> matcher(charset);
merge_charset(matcher.charset_, chset, tr);
return make_dynamic<BidiIter>(matcher);
}
}
// special case to make [[:digit:]] fast
else if(chset.base().empty() && chset.posix_no().empty())
{
BOOST_ASSERT(0 != chset.posix_yes());
posix_charset_matcher<Traits> matcher(chset.posix_yes(), chset.is_inverted());
return make_dynamic<BidiIter>(matcher);
}
// default, slow
else
{
if(icase)
{
charset_matcher<Traits, mpl::true_> matcher(chset);
return make_dynamic<BidiIter>(matcher);
}
else
{
charset_matcher<Traits, mpl::false_> matcher(chset);
return make_dynamic<BidiIter>(matcher);
}
}
}
inline void merge_charset
(
basic_chset<Char> &basic
, compound_charset<Traits> const &compound
, Traits const &tr
)
{
detail::ignore_unused(tr);
if(0 != compound.posix_yes())
{
typename Traits::char_class_type mask = compound.posix_yes();
for(int i = 0; i <= static_cast<int>(UCHAR_MAX); ++i)
{
if(tr.isctype((Char)i, mask))
{
basic.set((Char)i);
}
}
}
if(!compound.posix_no().empty())
{
for(std::size_t j = 0; j < compound.posix_no().size(); ++j)
{
typename Traits::char_class_type mask = compound.posix_no()[j];
for(int i = 0; i <= static_cast<int>(UCHAR_MAX); ++i)
{
if(!tr.isctype((Char)i, mask))
{
basic.set((Char)i);
}
}
}
}
if(compound.is_inverted())
{
basic.inverse();
}
}