problem with extracting data from file

[xtrashild]

Hello, I'm trying to extract data from a text file and writing them to a vector of testLine objects

but getting errors:
filesbehandlung.cpp:47:3: error: unknown type name 'testLine'
testLine t{ (greeting, fruit, v1, v2) }
^
filesbehandlung.cpp:47:16: warning: expression result unused [-Wunused-value]
testLine t{ (greeting, fruit, v1, v2) }
^~~~~~~~
filesbehandlung.cpp:47:26: warning: expression result unused [-Wunused-value]
testLine t{ (greeting, fruit, v1, v2) }
^~~~~
filesbehandlung.cpp:47:33: warning: expression result unused [-Wunused-value]
testLine t{ (greeting, fruit, v1, v2) }
^~
filesbehandlung.cpp:47:42: error: expected ';' at end of declaration
testLine t{ (greeting, fruit, v1, v2) }
^
;
filesbehandlung.cpp:72:46: warning: expression result unused [-Wunused-value]
vector<testLine> test{dateiLesen<vector> > (test,"textfile.txt")};
^~~~
filesbehandlung.cpp:72:24: error: reference to overloaded function could not be resolved; did you mean to call it?
vector<testLine> test{dateiLesen<vector> > (test,"textfile.txt")};
^~~~~~~~~~~~~~~~~~
filesbehandlung.cpp:26:21: note: possible target for call
template<class T> T dateiLesen(string file) {
^
4 warnings and 3 errors generated.
here is my source code:

#include <iostream>
#include <fstream>
#include <iostream>
#include <string>
#include <iterator>
#include <sstream>
#include <vector>
#include <numeric>

using std::string;
using std::ifstream;
using std::ofstream;

using namespace std;

template<class T> T from_string(const string s) {
	std::stringstream ss{s};
	
	T val{};
	
	if(!(ss>>val)) {
		 cerr<<"failed to convert from string";
	}
	return val;
}
template<class T> T dateiLesen(string file) {
	ifstream is{file.c_str()};
	std::istream_iterator<string> file_it{is};
	std::istream_iterator<string> eof{};
	
	T testl{};
	while(file_it!= eof && is){
		string greeting{*file_it};
		file_it++;
		
		string fruit{*file_it};
		file_it++;
		
		string val1{*file_it};
		file_it++;
		int v1{ from_string<int>(val1.substr(1, string::npos))};
		
		string val2{*file_it};
		file_it++;
		int v2{ from_string<int>(val2.substr(1, string::npos))};
		
		testLine t{ (greeting, fruit, v1, v2) }
		testl.push_back(t);
		
		return testl;
	}
}

enum Greeting{
	hello =1, goodbye
};
class testLine{

public:
	testLine() : greeting{hello}, fruit{}, value1{}, value2{} {	
	}
	testLine(Greeting g, string f,int v1,int v2): greeting{g}, fruit{f}, value1{v1}, value2{v2} {}	
private:
	Greeting greeting;
	string fruit;
	int value1{};
	int value2{};
	
};

int main(int argc, char *argv[]) {
	vector<testLine> test{dateiLesen<vector> > (test,"textfile.txt")};
	return 0;
		
	
}

txt file contains :
hello apple 3 5
goodbye pineapple 5 2
hello banana 6 20

thanks for your help

[Repeater]

The compiler starts at the top and reads downwards. It needs to know about an object before you can use it.

It reaches this line:
testLine t{ (greeting, fruit, v1, v2) }
in which you are attempting to create an object of type testLine, but the compiler has never heard of it. Doesn't know what a "testLine" object is.

Put your defintion of testLine before you use one.

[xtrashild]

#include <iostream>
#include <fstream>
#include <iostream>
#include <string>
#include <iterator>
#include <sstream>
#include <vector>
#include <numeric>

using std::string;
using std::ifstream;
using std::ofstream;

using namespace std;
enum Greeting{
	hello =1, goodbye
};
class testLine{

public:
	testLine() : greeting{hello}, fruit{}, value1{}, value2{} {	
	}
	testLine(Greeting g, string f,int v1,int v2): greeting{g}, fruit{f}, value1{v1}, value2{v2} {}	
private:
	Greeting greeting;
	string fruit;
	int value1{};
	int value2{};
	
};


template<class T> T from_string(const string s) {
	std::stringstream ss{s};
	
	T val{};
	
	if(!(ss>>val)) {
		 cerr<<"failed to convert from string";
	}
	return val;
}
template<class T> T dateiLesen(string file) {
	ifstream is{file.c_str()};
	std::istream_iterator<string> file_it{is};
	std::istream_iterator<string> eof{};
	
	T testl{};
	while(file_it!= eof && is){
		string greeting{*file_it};
		file_it++;
		
		string fruit{*file_it};
		file_it++;
		
		string val1{*file_it};
		file_it++;
		int v1{ from_string<int>(val1.substr(1, string::npos))};
		
		string val2{*file_it};
		file_it++;
		int v2{ from_string<int>(val2.substr(1, string::npos))};
		
		testLine t{ (greeting, fruit, v1, v2) }
		testl.push_back(t);
		
		return testl;
	}
}


int main(int argc, char *argv[]) {
	vector<testLine> test{dateiLesen<vector> > (test,"textfile.txt")};
	return 0;
	
}

errors: filesbehandlung.cpp:65:16: warning: expression result unused [-Wunused-value]
testLine t{ (greeting, fruit, v1, v2) }
^~~~~~~~
filesbehandlung.cpp:65:26: warning: expression result unused [-Wunused-value]
testLine t{ (greeting, fruit, v1, v2) }
^~~~~
filesbehandlung.cpp:65:33: warning: expression result unused [-Wunused-value]
testLine t{ (greeting, fruit, v1, v2) }
^~
filesbehandlung.cpp:65:12: error: no matching constructor for initialization of 'testLine'
testLine t{ (greeting, fruit, v1, v2) }
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
filesbehandlung.cpp:19:7: note: candidate constructor (the implicit move constructor) not viable: no known conversion from 'int' to 'testLine' for 1st argument
class testLine{
^
filesbehandlung.cpp:19:7: note: candidate constructor (the implicit copy constructor) not viable: no known conversion from 'int' to 'const testLine' for 1st argument
class testLine{
^
filesbehandlung.cpp:22:2: note: candidate constructor not viable: requires 0 arguments, but 1 was provided
testLine() : greeting{hello}, fruit{}, value1{}, value2{} {
^
filesbehandlung.cpp:24:2: note: candidate constructor not viable: requires 4 arguments, but 1 was provided
testLine(Greeting g, string f,int v1,int v2): greeting{g}, fruit{f}, value1{v1}, value2{v2} {}
^
filesbehandlung.cpp:65:42: error: expected ';' at end of declaration
testLine t{ (greeting, fruit, v1, v2) }
^
;
filesbehandlung.cpp:74:46: warning: expression result unused [-Wunused-value]
vector<testLine> test{dateiLesen<vector> > (test,"textfile.txt")};
^~~~
filesbehandlung.cpp:74:24: error: reference to overloaded function could not be resolved; did you mean to call it?
vector<testLine> test{dateiLesen<vector> > (test,"textfile.txt")};
^~~~~~~~~~~~~~~~~~
filesbehandlung.cpp:44:21: note: possible target for call
template<class T> T dateiLesen(string file) {
^
4 warnings and 3 errors generated.

[dhayden]

Line 64 should be testLine t{ greeting, fruit, v1, v2 };.

Line 73: Can you explain what you're trying to do here?