lyx_mirror/boost/libs/regex/src/primary_transform.hpp
Lars Gullik Bjønnes 86a566a27d add the boost regex sources and create the libboostregex lib
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@4202 a592a061-630c-0410-9148-cb99ea01b6c8
2002-05-24 12:53:12 +00:00

121 lines
2.9 KiB
C++

/*
*
* Copyright (c) 1998-2002
* Dr John Maddock
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Dr John Maddock makes no representations
* about the suitability of this software for any purpose.
* It is provided "as is" without express or implied warranty.
*
*/
/*
* LOCATION: see http://www.boost.org for most recent version.
* FILE: primary_transform.hpp
* VERSION: see <boost/version.hpp>
* DESCRIPTION: Heuristically determines the sort string format in use
* by the current locale.
*/
namespace boost{
namespace re_detail{
enum{
sort_C,
sort_fixed,
sort_delim,
sort_unknown
};
template <class S, class charT>
unsigned count_chars(const S& s, charT c)
{
unsigned int count = 0;
for(unsigned pos = 0; pos < s.size(); ++pos)
{
if(s[pos] == c) ++count;
}
return count;
}
template <class traits, class charT>
unsigned find_sort_syntax(const traits* pt, charT* delim)
{
//
// compare 'a' with 'A' to see how similar they are,
// should really use a-accute but we can't portably do that,
//
typedef typename traits::string_type string_type;
typedef typename traits::char_type char_type;
// Suppress incorrect warning for MSVC
(void)pt;
string_type a(1, (char_type)'a');
string_type sa;
pt->transform(sa, a);
if(sa == a)
{
*delim = 0;
return sort_C;
}
string_type A(1, (char_type)'A');
string_type sA;
pt->transform(sA, A);
string_type c(1, (char_type)';');
string_type sc;
pt->transform(sc, c);
int pos = 0;
while((pos <= static_cast<int>(sa.size())) && (pos <= static_cast<int>(sA.size())) && (sa[pos] == sA[pos])) ++pos;
--pos;
if(pos < 0)
{
*delim = 0;
return sort_unknown;
}
//
// at this point sa[pos] is either the end of a fixed with field
// or the character that acts as a delimiter:
//
charT maybe_delim = sa[pos];
if((pos != 0) && (count_chars(sa, maybe_delim) == count_chars(sA, maybe_delim)) && (count_chars(sa, maybe_delim) == count_chars(c, maybe_delim)))
{
*delim = maybe_delim;
return sort_delim;
}
//
// OK doen't look like a delimiter, try for fixed width field:
//
if((sa.size() == sA.size()) && (sa.size() == c.size()))
{
// note assumes that the fixed width field is less than
// numeric_limits<charT>::max(), should be true for all types
// I can't imagine 127 character fields...
*delim = static_cast<charT>(++pos);
return sort_fixed;
}
//
// don't know what it is:
//
*delim = 0;
return sort_unknown;
}
} // namespace re_detail
} // namespace boost