Compiling errors, unsure of whats wrong

[jonrogers44]

The code I have works fine in the Visual compiler, but will not compile in g++. Its 3 files. The header file, the main , and another... the error that keeps appearing is "invalid initialization of non-const ref"....

I will post the header and definition class, any help is appreciated as I am a novice programer


Header:

#include<iostream>
#include<fstream>

using namespace std;

#ifndef DOCUMENT_H
#define DOCUMENT_H

class Document{


friend ostream& operator<<(ostream&, Document&);
friend istream& operator>>(istream&, Document&);

// private variables not accessible to the client
private: char *ptr;
int data;
static const int size = 5000;
public:
Document(); //Default
Document(Document&); // copy constructor
int countWords();
int length();
Document operator=(Document&);
Document operator=(const string&);
char operator[](int);
Document operator+(Document&);

};

#endif

Definition class


#include"Document.h"

using namespace std;

//defualt constructor creating dynamic array and setting its size, as well as setting length to zero
Document::Document(){

ptr = new char[size];
ptr[0] = '\0';
data = 0;

}


Document::Document(Document& d1){

ptr = new char[size];
data = d1.length();

for (int i = 0; i < data; i++){
ptr[i] = d1[i];

}
ptr[data] = '\0';

}

int Document::countWords(){
int counter = 0;


for (int i = 0; i < data; i++){


if (ptr[i] <= ' ' || ptr[i] == ',' || ptr[i] == ';' || ptr[i] == ':' || ptr[i] == '-' || ptr[i] == '.'){

counter++;

while (ptr[i] <= ' ' || ptr[i] == ',' || ptr[i] == ';' || ptr[i] == ':' || ptr[i] == '-' || ptr[i] == '.')

i++;
}

}

if (ptr[data - 1] != ' ' || ptr[data - 1] != ',' || ptr[data - 1] != ';' || ptr[data - 1] != ':' || ptr[data - 1] != '-' || ptr[data - 1] != '.')

counter++;

return counter;

}


int Document::length(){

int count = 0;

while (ptr[count] != '\0'){

count++;
}

return count;


}

Document Document::operator=(Document& d1){


data = d1.length();

for (int i = 0; i < data; i++)
ptr[i] = d1[i];

ptr[data] = '\0';

return *this;

}


Document Document::operator=(const string& d1){

data = d1.length();

for (int i = 0; i < data; i++)

ptr[i] = d1[i];

ptr[data] = '\0';

return *this;


}

ostream& operator<<(ostream& out, Document& d1){

int data = d1.length();
for (int i = 0; i < data; i++)
out << d1[i];

return out;

}

istream& operator>>(istream &in, Document &d1){



in.getline(d1.ptr, d1.size, '\0');
return in;
}

char Document::operator[](int count){

return ptr[count];


}

Document Document::operator+(Document& d1){

Document d2 = (*this);

int trial = d1.length();
int oldLength = d2.length();


//for (int i = 0; i < oldLength; i++){
// d2.ptr[i] = (*this)[i];
// }

for (int i = 0; i < trial; i++){
d2.ptr[i + oldLength] = d1[i];
}
trial = trial + oldLength;
d2.ptr[trial] = '\0';
return d2;
}

[TheIdeasMan]

Hi,

What was the entire command you used to compile with g++ ?

If you have errors please post them here verbatim.

Please use code tags: http://www.cplusplus.com/articles/z13hAqkS/

Good Luck !!

[jonrogers44]

the entire command was g++ prog6.cpp document.cpp -o prog6

the errors that I got are all on the + operator overload fcn and they state

prog6.cpp:38:14: error: invalid initialization of non-const reference of type ‘D ocument&’ from an rvalue of type ‘Document’
doc2 = doc2 + doc1;

[TheIdeasMan]

Hi,

It would be easier if you edited your post, select the code, then press the <> button. This will use code tags. Then we get line numbers, keywords and can compile it right here with cpp.sh - the gear icon top right of the code snippet.

You should compile with a high level of warnings and with the latest standard, as a minimum:

g++ -std=c++14 - Wall -Wextra -pedantic-errors *.cpp -o prog6

If your compiler can't do c++14, then try try c++11. Or it's easy to upgrade to the latest gcc.

There are even more warnings that aren't turned on even with the above options:
http://www.cplusplus.com/forum/general/183731/#msg899203

Can we have your file with main in it, then I can compile myself?

As well can you provide all the error warnings?

A link to operator+ http://en.cppreference.com/w/cpp/language/operators their implementation is different to yours.

You could also implement operator+=

[jonrogers44]

Thank you all, but with the help of a friend I did figure it out, HOWEVER, I will in the future use the coding blocks as was asked of me. Again thank you!

[TheIdeasMan]

Hi,

Just out of interest, what was the problem? The way you wrote the function?

[jonrogers44]

I apologize, I did not see this point until now, it was partly the fcn and the other part was the I actually forgot to bring the text file I was trying to read over into Linux as well....