Modifying a while loop that contains a break statement - c++

Question

I'm currently trying to write a loop to keep extracting each line from an input file using getline, and keep running until it detects the end of a paragraph.
I found this as a reference:
while (getline(inFile, line))
{
if (line.empty())
break;
else
{
for (int j = 0; j < line.length(); j++)
{
//Doing stuff here
}
}
}
I've tested this and it runs fine. However, I'm not allowed to use break statements for my assignment.
I thought I could do something like this:
while (getline(inFile, line))
{
while (!line.empty())
{
for (unsigned int i = 0; i < line.length(); i++)
{
//Do stuff
}
}
}
But the program ends up crashes when the loop iterates for the first time. I was wondering if anyone had some input how I could resolve this issue

Answer 1

This is how you solve it:
while (getline(inFile, line) && !line.empty()) { ... }
it has the exact same effect and it arguably improves the readability. The problem with your approach is that it causes an infinite loop. The fact that line.empty() evaluates false does not effect the outer while there.

Answer 2

The following also demonstrates the use of a stringstream for testing. exec contains 3 tests snippets.
int exec(int , char** )
{
int retVal = 0;
cout << "\n\n";
string s =
" now is the time\n"
" for all good men\n"
"\n" // empty line
" to come to the aid \n"; // eof()
// solution 1 has infinite loop
if(0) // disable
{
stringstream ss;
ss << s; // load ss
string line;
while (getline(ss, line))
{
while (!line.empty())
{
for (uint j=0; j < line.length(); ++j)
cout << line[j];
}
cout << endl;
}
}
// solution 2 exits too soon, line 3 is empty, line 4 dropped
{
cout << "\n\n";
stringstream ss;
ss << s; // load ss
string line;
while (getline(ss, line) && !line.empty())
{
cout << line << endl;
}
}
// output:
// now is the time
// for all good men
// solution 3 - small test effort, but seems to work
{
cout << "\n\n";
stringstream ss;
ss << s; // load ss
do
{
string line;
getline(ss, line); // read a line
if (!line.empty()) // test it has content
cout << line << endl; // use when non-empty
} while(!ss.eof()); // how continue when file has more lines
} // solution 3 seems to work
// output:
// now is the time
// for all good men
// to come to the aid
return retVal;
}