Stringstream repeating first word

MrPickle · #1 (**permalink**) 10-11-2008, 12:46 PM

I am tokenizing a line using a stringstream and a vector but the stringstream seems to be repeating the first word, here's my code:

Code:

std::stringstream ss;
std::vector<std::string> LineVec;
std::string Line, Word;
while(std::getline(File, Line)) {
   if(Line.empty()) { continue; }
   ss.str(Line);
   ss.seekg(std::ios::beg);
   while(ss >> Word) { LineVec.push_back(Word); }

   //Un related stuff here

   LineVec.clear();
}

Here's an example input-output

Quote:

Input: Hello, My name's MrPickle
Output: Hello,
My
name's
MrPickle
Hello,

Bench · #2 (**permalink**) 10-11-2008, 05:03 PM

There's nothing obviously wrong with the code you've posted, perhaps you could post a more complete example program which displays the problem.

As an aside, you have a couple of redundant lines of code there; namely

Code:

   ss.seekg(std::ios::beg);

will effectively do nothing, since the ss object was only just initialised in the previous statement, and will already be set at the beginning (though it shouldn't do any harm either)
also

Code:

   if(Line.empty()) { continue; }

will never yield true, since Line would only be empty if your call to getline failed - at which point, the while loop would not actually run anyway

However, neither of these will affect the output you're seeing; I suspect the problem is either related to your File, or to the way you're directing output from your program

MrPickle · #3 (**permalink**) 10-11-2008, 06:04 PM

Without the seekg it doesn't output the later lines, here's an example I made to show that: Example.zip

I don't know what I'm doing to get it to output the first character twice, here's my exact code:

Code:

template<typename T>
T FromStringTo(std::string String) { return boost::lexical_cast<T>(String); }

void StringReplace(std::string *String, std::string Strip, std::string Replace) {
	int Position = String->find(Strip);
	while(Position != String->npos) {
		String->replace(Position, 1, Replace);
		Position = String->find(Strip, Position + 1);
	}
}

Obj::Obj(std::string Filename) {
		Loaded = false;
		std::ofstream Out("Obj.txt");
		std::ifstream File(Filename.c_str(), std::ios::in);
		if(!File.is_open()) { std::runtime_error("Unable to open \"" + Filename + "\""); exit(1); }

		std::string Line, Word, Type;
		std::stringstream LStream;
		std::vector<std::string> LVector;
		Vertex V;
		Polygon P;
		while(std::getline(File, Line)) {
			if(Line.empty()) { continue; }
			StringReplace(&Line, "/", " ");
			LStream.str(Line);
			LStream.seekg(std::ios::beg);
			Out << "----------------------------------------------\n" << Line << "\n"; Out.flush();
			while(LStream >> Word) { LVector.push_back(Word); }
			for(int i = 0; i < LVector.size(); i++) Out << LVector[i] << "\n"; Out.flush();

			Type = LVector.at(0);
			Out << Type << "\n";
			if(Type == "v") {
				V.x = FromStringTo<float>(LVector.at(1));
				V.y = FromStringTo<float>(LVector.at(2));
				V.z = FromStringTo<float>(LVector.at(3));
				Vertices.push_back(V);
			} else if(Type == "f") {
				switch(LVector.size()) {
					case 4:
						for(int i = 0; i < 3; i++) {
							P.Vertices[i] = FromStringTo<int>(LVector.at(i + 1));
						}
					case 7:
						for(int i = 0; i < 3; i++) {
							P.Vertices[i] = FromStringTo<int>(LVector.at(2 * i + 1));
						}
					case 10:
						for(int i = 0; i < 3; i++) {
							P.Vertices[i] = FromStringTo<int>(LVector.at(3 * i + 1));
						}
				}
				Faces.push_back(P);
				Out << LVector.size() << "\n";
			}
			LVector.clear();
		}
		Path = Filename;
		Loaded = true;
		Out.flush();
	}

MrPickle · #4 (**permalink**) 10-12-2008, 05:33 AM

Ok, I was being stupid. I am outputting the first word of the vector a few lines down. DOH.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

The Following User Says Thank You to Bench For This Useful Post:
MrPickle (10-12-2008)