boost/xpressive/detail/dynamic/parser_traits.hpp
///////////////////////////////////////////////////////////////////////////////
// detail/dynamic/parser_traits.hpp
//
// Copyright 2007 Eric Niebler. Distributed under 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)
#ifndef BOOST_XPRESSIVE_DETAIL_DYNAMIC_PARSER_TRAITS_HPP_EAN_10_04_2005
#define BOOST_XPRESSIVE_DETAIL_DYNAMIC_PARSER_TRAITS_HPP_EAN_10_04_2005
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
#include <string>
#include <climits>
#include <boost/assert.hpp>
#include <boost/throw_exception.hpp>
#include <boost/xpressive/regex_error.hpp>
#include <boost/xpressive/regex_traits.hpp>
#include <boost/xpressive/detail/detail_fwd.hpp>
#include <boost/xpressive/detail/dynamic/matchable.hpp>
#include <boost/xpressive/detail/dynamic/parser_enum.hpp>
#include <boost/xpressive/detail/utility/literals.hpp>
#include <boost/xpressive/detail/utility/algorithm.hpp>
namespace boost { namespace xpressive
{
///////////////////////////////////////////////////////////////////////////////
// compiler_traits
// this works for char and wchar_t. it must be specialized for anything else.
//
template<typename RegexTraits>
struct compiler_traits
{
typedef RegexTraits regex_traits;
typedef typename regex_traits::char_type char_type;
typedef typename regex_traits::string_type string_type;
typedef typename regex_traits::locale_type locale_type;
///////////////////////////////////////////////////////////////////////////////
// constructor
explicit compiler_traits(RegexTraits const &traits = RegexTraits())
: traits_(traits)
, flags_(regex_constants::ECMAScript)
, space_(lookup_classname(traits_, "space"))
, alnum_(lookup_classname(traits_, "alnum"))
{
}
///////////////////////////////////////////////////////////////////////////////
// flags
regex_constants::syntax_option_type flags() const
{
return this->flags_;
}
///////////////////////////////////////////////////////////////////////////////
// flags
void flags(regex_constants::syntax_option_type flags)
{
this->flags_ = flags;
}
///////////////////////////////////////////////////////////////////////////////
// traits
regex_traits &traits()
{
return this->traits_;
}
regex_traits const &traits() const
{
return this->traits_;
}
///////////////////////////////////////////////////////////////////////////////
// imbue
locale_type imbue(locale_type const &loc)
{
locale_type oldloc = this->traits().imbue(loc);
this->space_ = lookup_classname(this->traits(), "space");
this->alnum_ = lookup_classname(this->traits(), "alnum");
return oldloc;
}
///////////////////////////////////////////////////////////////////////////////
// getloc
locale_type getloc() const
{
return this->traits().getloc();
}
///////////////////////////////////////////////////////////////////////////////
// get_token
// get a token and advance the iterator
template<typename FwdIter>
regex_constants::compiler_token_type get_token(FwdIter &begin, FwdIter end)
{
using namespace regex_constants;
if(this->eat_ws_(begin, end) == end)
{
return regex_constants::token_end_of_pattern;
}
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, '\\'): return this->get_escape_token(++begin, end);
case BOOST_XPR_CHAR_(char_type, '.'): ++begin; return token_any;
case BOOST_XPR_CHAR_(char_type, '^'): ++begin; return token_assert_begin_line;
case BOOST_XPR_CHAR_(char_type, '$'): ++begin; return token_assert_end_line;
case BOOST_XPR_CHAR_(char_type, '('): ++begin; return token_group_begin;
case BOOST_XPR_CHAR_(char_type, ')'): ++begin; return token_group_end;
case BOOST_XPR_CHAR_(char_type, '|'): ++begin; return token_alternate;
case BOOST_XPR_CHAR_(char_type, '['): ++begin; return token_charset_begin;
case BOOST_XPR_CHAR_(char_type, ']'): ++begin; return token_charset_end;
case BOOST_XPR_CHAR_(char_type, '*'):
case BOOST_XPR_CHAR_(char_type, '+'):
case BOOST_XPR_CHAR_(char_type, '?'):
return token_invalid_quantifier;
case BOOST_XPR_CHAR_(char_type, '{'):
default:
return token_literal;
}
}
///////////////////////////////////////////////////////////////////////////////
// get_quant_spec
template<typename FwdIter>
bool get_quant_spec(FwdIter &begin, FwdIter end, detail::quant_spec &spec)
{
using namespace regex_constants;
FwdIter old_begin;
if(this->eat_ws_(begin, end) == end)
{
return false;
}
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, '*'):
spec.min_ = 0;
spec.max_ = (std::numeric_limits<unsigned int>::max)();
break;
case BOOST_XPR_CHAR_(char_type, '+'):
spec.min_ = 1;
spec.max_ = (std::numeric_limits<unsigned int>::max)();
break;
case BOOST_XPR_CHAR_(char_type, '?'):
spec.min_ = 0;
spec.max_ = 1;
break;
case BOOST_XPR_CHAR_(char_type, '{'):
old_begin = this->eat_ws_(++begin, end);
spec.min_ = spec.max_ = detail::toi(begin, end, this->traits());
detail::ensure
(
begin != old_begin && begin != end, error_brace, "invalid quantifier"
);
if(*begin == BOOST_XPR_CHAR_(char_type, ','))
{
old_begin = this->eat_ws_(++begin, end);
spec.max_ = detail::toi(begin, end, this->traits());
detail::ensure
(
begin != end && BOOST_XPR_CHAR_(char_type, '}') == *begin
, error_brace, "invalid quantifier"
);
if(begin == old_begin)
{
spec.max_ = (std::numeric_limits<unsigned int>::max)();
}
else
{
detail::ensure
(
spec.min_ <= spec.max_, error_badbrace, "invalid quantification range"
);
}
}
else
{
detail::ensure
(
BOOST_XPR_CHAR_(char_type, '}') == *begin, error_brace, "invalid quantifier"
);
}
break;
default:
return false;
}
spec.greedy_ = true;
if(this->eat_ws_(++begin, end) != end && BOOST_XPR_CHAR_(char_type, '?') == *begin)
{
++begin;
spec.greedy_ = false;
}
return true;
}
///////////////////////////////////////////////////////////////////////////
// get_group_type
template<typename FwdIter>
regex_constants::compiler_token_type get_group_type(FwdIter &begin, FwdIter end, string_type &name)
{
using namespace regex_constants;
if(this->eat_ws_(begin, end) != end && BOOST_XPR_CHAR_(char_type, '?') == *begin)
{
this->eat_ws_(++begin, end);
detail::ensure(begin != end, error_paren, "incomplete extension");
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, ':'): ++begin; return token_no_mark;
case BOOST_XPR_CHAR_(char_type, '>'): ++begin; return token_independent_sub_expression;
case BOOST_XPR_CHAR_(char_type, '#'): ++begin; return token_comment;
case BOOST_XPR_CHAR_(char_type, '='): ++begin; return token_positive_lookahead;
case BOOST_XPR_CHAR_(char_type, '!'): ++begin; return token_negative_lookahead;
case BOOST_XPR_CHAR_(char_type, 'R'): ++begin; return token_recurse;
case BOOST_XPR_CHAR_(char_type, '$'):
this->get_name_(++begin, end, name);
detail::ensure(begin != end, error_paren, "incomplete extension");
if(BOOST_XPR_CHAR_(char_type, '=') == *begin)
{
++begin;
return token_rule_assign;
}
return token_rule_ref;
case BOOST_XPR_CHAR_(char_type, '<'):
this->eat_ws_(++begin, end);
detail::ensure(begin != end, error_paren, "incomplete extension");
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, '='): ++begin; return token_positive_lookbehind;
case BOOST_XPR_CHAR_(char_type, '!'): ++begin; return token_negative_lookbehind;
default:
boost::throw_exception(regex_error(error_badbrace, "unrecognized extension"));
}
case BOOST_XPR_CHAR_(char_type, 'P'):
this->eat_ws_(++begin, end);
detail::ensure(begin != end, error_paren, "incomplete extension");
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, '<'):
this->get_name_(++begin, end, name);
detail::ensure(begin != end && BOOST_XPR_CHAR_(char_type, '>') == *begin++, error_paren, "incomplete extension");
return token_named_mark;
case BOOST_XPR_CHAR_(char_type, '='):
this->get_name_(++begin, end, name);
detail::ensure(begin != end, error_paren, "incomplete extension");
return token_named_mark_ref;
default:
boost::throw_exception(regex_error(error_badbrace, "unrecognized extension"));
}
case BOOST_XPR_CHAR_(char_type, 'i'):
case BOOST_XPR_CHAR_(char_type, 'm'):
case BOOST_XPR_CHAR_(char_type, 's'):
case BOOST_XPR_CHAR_(char_type, 'x'):
case BOOST_XPR_CHAR_(char_type, '-'):
return this->parse_mods_(begin, end);
default:
boost::throw_exception(regex_error(error_badbrace, "unrecognized extension"));
}
}
return token_literal;
}
//////////////////////////////////////////////////////////////////////////
// get_charset_token
// NOTE: white-space is *never* ignored in a charset.
template<typename FwdIter>
regex_constants::compiler_token_type get_charset_token(FwdIter &begin, FwdIter end)
{
using namespace regex_constants;
BOOST_ASSERT(begin != end);
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, '^'): ++begin; return token_charset_invert;
case BOOST_XPR_CHAR_(char_type, '-'): ++begin; return token_charset_hyphen;
case BOOST_XPR_CHAR_(char_type, ']'): ++begin; return token_charset_end;
case BOOST_XPR_CHAR_(char_type, '['):
{
FwdIter next = begin; ++next;
if(next != end && *next == BOOST_XPR_CHAR_(char_type, ':'))
{
begin = ++next;
return token_posix_charset_begin;
}
}
break;
case BOOST_XPR_CHAR_(char_type, ':'):
{
FwdIter next = begin; ++next;
if(next != end && *next == BOOST_XPR_CHAR_(char_type, ']'))
{
begin = ++next;
return token_posix_charset_end;
}
}
break;
case BOOST_XPR_CHAR_(char_type, '\\'):
if(++begin != end)
{
switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, 'b'): ++begin; return token_charset_backspace;
default:;
}
}
return token_escape;
default:;
}
return token_literal;
}
//////////////////////////////////////////////////////////////////////////
// get_escape_token
template<typename FwdIter>
regex_constants::compiler_token_type get_escape_token(FwdIter &begin, FwdIter end)
{
using namespace regex_constants;
if(begin != end)
{
switch(*begin)
{
//case BOOST_XPR_CHAR_(char_type, 'a'): ++begin; return token_escape_bell;
//case BOOST_XPR_CHAR_(char_type, 'c'): ++begin; return token_escape_control;
//case BOOST_XPR_CHAR_(char_type, 'e'): ++begin; return token_escape_escape;
//case BOOST_XPR_CHAR_(char_type, 'f'): ++begin; return token_escape_formfeed;
//case BOOST_XPR_CHAR_(char_type, 'n'): ++begin; return token_escape_newline;
//case BOOST_XPR_CHAR_(char_type, 't'): ++begin; return token_escape_horizontal_tab;
//case BOOST_XPR_CHAR_(char_type, 'v'): ++begin; return token_escape_vertical_tab;
case BOOST_XPR_CHAR_(char_type, 'A'): ++begin; return token_assert_begin_sequence;
case BOOST_XPR_CHAR_(char_type, 'b'): ++begin; return token_assert_word_boundary;
case BOOST_XPR_CHAR_(char_type, 'B'): ++begin; return token_assert_not_word_boundary;
case BOOST_XPR_CHAR_(char_type, 'E'): ++begin; return token_quote_meta_end;
case BOOST_XPR_CHAR_(char_type, 'Q'): ++begin; return token_quote_meta_begin;
case BOOST_XPR_CHAR_(char_type, 'Z'): ++begin; return token_assert_end_sequence;
// Non-standard extension to ECMAScript syntax
case BOOST_XPR_CHAR_(char_type, '<'): ++begin; return token_assert_word_begin;
case BOOST_XPR_CHAR_(char_type, '>'): ++begin; return token_assert_word_end;
default:; // fall-through
}
}
return token_escape;
}
private:
//////////////////////////////////////////////////////////////////////////
// parse_mods_
template<typename FwdIter>
regex_constants::compiler_token_type parse_mods_(FwdIter &begin, FwdIter end)
{
using namespace regex_constants;
bool set = true;
do switch(*begin)
{
case BOOST_XPR_CHAR_(char_type, 'i'): this->flag_(set, icase_); break;
case BOOST_XPR_CHAR_(char_type, 'm'): this->flag_(!set, single_line); break;
case BOOST_XPR_CHAR_(char_type, 's'): this->flag_(!set, not_dot_newline); break;
case BOOST_XPR_CHAR_(char_type, 'x'): this->flag_(set, ignore_white_space); break;
case BOOST_XPR_CHAR_(char_type, ':'): ++begin; // fall-through
case BOOST_XPR_CHAR_(char_type, ')'): return token_no_mark;
case BOOST_XPR_CHAR_(char_type, '-'): if(false == (set = !set)) break; // else fall-through
default: boost::throw_exception(regex_error(error_paren, "unknown pattern modifier"));
}
while(detail::ensure(++begin != end, error_paren, "incomplete extension"));
// this return is technically unreachable, but this must
// be here to work around a bug in gcc 4.0
return token_no_mark;
}
///////////////////////////////////////////////////////////////////////////////
// flag_
void flag_(bool set, regex_constants::syntax_option_type flag)
{
this->flags_ = set ? (this->flags_ | flag) : (this->flags_ & ~flag);
}
///////////////////////////////////////////////////////////////////////////
// is_space_
bool is_space_(char_type ch) const
{
return 0 != this->space_ && this->traits().isctype(ch, this->space_);
}
///////////////////////////////////////////////////////////////////////////
// is_alnum_
bool is_alnum_(char_type ch) const
{
return 0 != this->alnum_ && this->traits().isctype(ch, this->alnum_);
}
///////////////////////////////////////////////////////////////////////////
// get_name_
template<typename FwdIter>
void get_name_(FwdIter &begin, FwdIter end, string_type &name)
{
this->eat_ws_(begin, end);
for(name.clear(); begin != end && this->is_alnum_(*begin); ++begin)
{
name.push_back(*begin);
}
this->eat_ws_(begin, end);
detail::ensure(!name.empty(), regex_constants::error_paren, "incomplete extension");
}
///////////////////////////////////////////////////////////////////////////////
// eat_ws_
template<typename FwdIter>
FwdIter &eat_ws_(FwdIter &begin, FwdIter end)
{
if(0 != (regex_constants::ignore_white_space & this->flags()))
{
while(end != begin && (BOOST_XPR_CHAR_(char_type, '#') == *begin || this->is_space_(*begin)))
{
if(BOOST_XPR_CHAR_(char_type, '#') == *begin++)
{
while(end != begin && BOOST_XPR_CHAR_(char_type, '\n') != *begin++) {}
}
else
{
for(; end != begin && this->is_space_(*begin); ++begin) {}
}
}
}
return begin;
}
regex_traits traits_;
regex_constants::syntax_option_type flags_;
typename regex_traits::char_class_type space_;
typename regex_traits::char_class_type alnum_;
};
}} // namespace boost::xpressive
#endif