Is using getline with a fstream reference covered in the standard?
I have three C++ compilers on my system. Two of them compile
the code below without warnings. The third returns the following
error:
t1.cpp:
Error E2285 t1.cpp 14: Could not find a match for
'std::getline<c harT,traits,All ocator>(std::if stream,std::str ing)'
in function A::readfun()
*** 1 errors in Compile ***
If the fstream is not a reference, it compiles without complaint.
BTW, yeah, I know, I haven't opened a file etc. I've
tried to skinny the code down to the minimum that
produes the error.
#include <fstream>
#include <string>
class A {
public:
A(std::ifstream & _inH) : inH(_inH) {}
void readfun();
void readfun1();
private:
std::ifstream& inH;
};
void A::readfun() {
std::string buf;
std::getline(in H, buf);
}
int main() {
std::ifstream fin;
class A x(fin);
return 0;
} 2 4257
"Peter Gordon" <petergo@_delet eme_.netspace.n et.au> wrote in message
news:Xn******** *************** ***********@203 .10.110.105... Is using getline with a fstream reference covered in the standard?
Yes.
I have three C++ compilers on my system. Two of them compile the code below without warnings. The third returns the following error: t1.cpp: Error E2285 t1.cpp 14: Could not find a match for 'std::getline<c harT,traits,All ocator>(std::if stream,std::str ing)' in function A::readfun()
'std::getline() 's first parameter is type 'std::ifstream& ' (that is,
a reference), not 'std::ifstream' (an object).
*** 1 errors in Compile ***
If the fstream is not a reference, it compiles without complaint.
Again, 'std::getline() 's first parameter is a reference.
Which compiler is giving that error message? BTW, yeah, I know, I haven't opened a file etc. I've tried to skinny the code down to the minimum that produes the error.
That's what we like. :-) #include <fstream> #include <string>
class A { public: A(std::ifstream & _inH) : inH(_inH) {} void readfun(); void readfun1(); private: std::ifstream& inH; }; void A::readfun() { std::string buf; std::getline(in H, buf); } int main() { std::ifstream fin; class A x(fin);
The keyword 'class' is redundant (but harmless) here.
return 0; }
The code looks OK to me. (But of course the call to 'getline()'
will always fail, since you didn't open the stream).
-Mike
"Mike Wahler" <mk******@mkwah ler.net> wrote in news:UKtZd.9167 $oO4.3964
@newsread3.news .pas.earthlink. net: "Peter Gordon" <petergo@_delet eme_.netspace.n et.au> wrote in message news:Xn******** *************** ***********@203 .10.110.105... Is using getline with a fstream reference covered in the standard?
Yes.
I have three C++ compilers on my system. Two of them compile the code below without warnings. The third returns the following error: t1.cpp: Error E2285 t1.cpp 14: Could not find a match for 'std::getline<c harT,traits,All ocator>(std::if stream,std::str ing)' in function A::readfun()
'std::getline() 's first parameter is type 'std::ifstream& ' (that is, a reference), not 'std::ifstream' (an object).
*** 1 errors in Compile ***
If the fstream is not a reference, it compiles without complaint.
Again, 'std::getline() 's first parameter is a reference.
Which compiler is giving that error message?
Borland Ver 55 which is their free download and is dated
about 2000.
I have a registered copy of CBuilder 4.
The following code compiled and linked on it.
void A::readfun() {
std::string buf;
ifstream inH1;
inH1 = inH;
std::getline(in H1, buf);
}
I didn't try to run it. <g>
So I downloaded the later version and it wouldn't
let me re-asign a reference thus, at least it is an
improvement.
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