我想解析字符串
std::string entry = "127.0.0.1 - [16/Aug/2012:01:50:02 +0000] \"GET /check.htm HTTP/1.1\" 200 17 \"AgentName/0.1 libwww-perl/5.833\""
具有以下内容:
ip_rule %= lexeme[(+char_("0-9."))[ref(ip) = _1]];
timestamp_rule %= lexeme[('[' >> +(char_ - ']') >> ']')[ref(timestamp) = _1]];
user_rule %= lexeme[(+char_)[ref(user) = _1]];
request_rule %= lexeme[('"' >> +(char_ - '"') >> '"')[ref(req) = _1]];
referer_rule %= lexeme[('"' >> +(char_ - '"') >> '"')[ref(referer) = _1]];
bool r = phrase_parse(first, last,
ip_rule >> user_rule >> timestamp_rule >> request_rule >> uint_[ref(status) = _1]
>> uint_[ref(transferred_bytes) = _1] >> referer_rule, space);
但它不匹配。如果我从字符串中删除“ - ”,并且规则“user_rule”当然比它匹配。你能否告诉我如何将字符串与“ - ”匹配?
答案 0 :(得分:3)
您的user_rule
“吃掉了”其他文字。像这样定义它:+~qi::char_("["))
,以便它停在'['
个字符处。
以下代码按预期工作:
#include <boost/spirit/include/qi.hpp>
using namespace boost::spirit::qi;
int main()
{
std::string ip, user, timestamp, req, referer;
unsigned status, transferred_bytes;
std::string entry = "127.0.0.1 - [16/Aug/2012:01:50:02 +0000] \"GET /check.htm HTTP/1.1\" 200 17 \"AgentName/0.1 libwww-perl/5.833\"";
bool r = phrase_parse(entry.begin(), entry.end(),
lexeme[+char_("0-9.")] >>
+~char_("[") >>
lexeme[('[' >> +~char_("]") >> ']')] >>
lexeme[('"' >> +~char_("\"") >> '"')] >>
uint_ >>
uint_ >>
lexeme[('"' >> +~char_("\"") >> '"')], space, ip, user, timestamp, req, status, transferred_bytes, referer);
}