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- /*
- *
- * Copyright (c) 1998-2002
- * John Maddock
- *
- * Use, modification and distribution are subject to the
- * Boost Software License, Version 1.0. (See accompanying file
- * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
- *
- */
-
- /*
- * 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.
- */
- #ifndef BOOST_REGEX_PRIMARY_TRANSFORM
- #define BOOST_REGEX_PRIMARY_TRANSFORM
- #ifdef BOOST_MSVC
- #pragma warning(push)
- #pragma warning(disable: 4103)
- #endif
- #ifdef BOOST_HAS_ABI_HEADERS
- # include BOOST_ABI_PREFIX
- #endif
- #ifdef BOOST_MSVC
- #pragma warning(pop)
- #endif
- namespace boost{
- namespace BOOST_REGEX_DETAIL_NS{
- enum{
- sort_C,
- sort_fixed,
- sort_delim,
- sort_unknown
- };
- template <class S, class charT>
- unsigned count_chars(const S& s, charT c)
- {
- //
- // Count how many occurrences of character c occur
- // in string s: if c is a delimeter between collation
- // fields, then this should be the same value for all
- // sort keys:
- //
- 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;
- char_type a[2] = {'a', '\0', };
- string_type sa(pt->transform(a, a+1));
- if(sa == a)
- {
- *delim = 0;
- return sort_C;
- }
- char_type A[2] = { 'A', '\0', };
- string_type sA(pt->transform(A, A+1));
- char_type c[2] = { ';', '\0', };
- string_type sc(pt->transform(c, c+1));
- 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 width 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(sc, 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() == sc.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 BOOST_REGEX_DETAIL_NS
- } // namespace boost
- #ifdef BOOST_MSVC
- #pragma warning(push)
- #pragma warning(disable: 4103)
- #endif
- #ifdef BOOST_HAS_ABI_HEADERS
- # include BOOST_ABI_SUFFIX
- #endif
- #ifdef BOOST_MSVC
- #pragma warning(pop)
- #endif
- #endif
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