std::regex issue

Natural_Bugger

hello, i trying to split a string witch contains a space into 2 parts..
i have the following code.

        std::string str{""};
        getline(cin, str);

        std::vector<std::string> tokens;
        std::regex re(" ");

        //start/end points of tokens in str
        std::sregex_token_iterator
        begin(str.begin(), str.end(), re),
        end;

        std::copy(begin, end, std::back_inserter(tokens));

        string first_value = tokens[0];
        std::cout << "first_value: " << first_value << std::endl;

        string second_value = tokens[1];
        std::cout << "second_value" << second_value << std::endl;

this is what the console outputs:

sadd asdda // test string 1
first_value:  
terminate called after throwing an instance of 'std::logic_error'
  what():  basic_string::_M_construct null not valid

according to debug mode:
the first value = ""
the second value = " \020" // 16 0x10

what's going on?

SGaist

Hi,

Using a regular expression in this case seems overkill.

What about the solution proposed in this Stack Overflow answer ?

Note that QString has a split method that would suite your purpose pretty nicely.

Natural_Bugger

@SGaist
hi, thnx for your reply,

afterwards, i found this one.
https://stackoverflow.com/questions/5844657/splitting-a-c-string-into-two-parts

        size_t found = str.find(" ");
        if(found != string::npos) {
            string temp1 = (str.substr(0,found));
            string temp2 = (str.substr(found+1, string::npos));
        }

it did the job.

i can't use the QT parts for these assignments.