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Added support for conditional expressions.

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[SVN r22744]
This commit is contained in:
John Maddock committed 2004-05-05 10:41:55 +00:00
1 parent d2c3ec6d57
commit b5cf51fbc6
9 files changed
+201 -16
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include/boost/regex/v4/basic_regex_parser.hpp
+56
View File
@@ -1127,6 +1127,7 @@ bool basic_regex_parser<charT, traits>::parse_perl_extension()
std::ptrdiff_t last_alt_point = m_alt_insert_point;
this->m_pdata->m_data.align();
m_alt_insert_point = this->m_pdata->m_data.size();
std::ptrdiff_t expected_alt_point = m_alt_insert_point;
//
// select the actual extension used:
//
@@ -1191,6 +1192,48 @@ bool basic_regex_parser<charT, traits>::parse_perl_extension()
this->m_pdata->m_data.align();
m_alt_insert_point = this->m_pdata->m_data.size();
break;
case regex_constants::syntax_open_mark:
{
// a conditional expression:
pb->index = markid = -4;
if(++m_position == m_end)
fail(REG_BADRPT, m_position - m_base);
int v = this->m_traits.toi(m_position, m_end, 10);
if(v > 0)
{
re_brace* br = static_cast<re_brace*>(this->append_state(syntax_element_assert_backref, sizeof(re_brace)));
br->index = v;
if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_close_mark)
fail(REG_BADRPT, m_position - m_base);
if(++m_position == m_end)
fail(REG_BADRPT, m_position - m_base);
}
else
{
// verify that we have a lookahead or lookbehind assert:
if(this->m_traits.syntax_type(*m_position) != regex_constants::syntax_question)
fail(REG_BADRPT, m_position - m_base);
if(++m_position == m_end)
fail(REG_BADRPT, m_position - m_base);
if(this->m_traits.syntax_type(*m_position) == regex_constants::escape_type_left_word)
{
if(++m_position == m_end)
fail(REG_BADRPT, m_position - m_base);
if((this->m_traits.syntax_type(*m_position) != regex_constants::syntax_equal)
&& (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_not))
fail(REG_BADRPT, m_position - m_base);
m_position -= 3;
}
else
{
if((this->m_traits.syntax_type(*m_position) != regex_constants::syntax_equal)
&& (this->m_traits.syntax_type(*m_position) != regex_constants::syntax_not))
fail(REG_BADRPT, m_position - m_base);
m_position -= 2;
}
}
break;
}
default:
fail(REG_BADRPT, m_position - m_base);
}
@@ -1221,6 +1264,19 @@ bool basic_regex_parser<charT, traits>::parse_perl_extension()
}
}
//
// verify that if this is conditional expression, that we do have
// an alternative, if not add one:
//
if(markid == -4)
{
re_syntax_base* b = this->getaddress(expected_alt_point);
if(b->type != syntax_element_alt)
{
re_alt* alt = static_cast<re_alt*>(this->insert_state(expected_alt_point, syntax_element_alt, sizeof(re_alt)));
alt->alt.i = this->m_pdata->m_data.size() - this->getoffset(alt);
}
}
//
// append closing parenthesis state:
//
pb = static_cast<re_brace*>(this->append_state(syntax_element_endmark, sizeof(re_brace)));