Question About Blank Lines in Text Files

Hello,

I was just curious how blank lines are handled when using getline? Say I have a text file as follows:

Quote:

---

Line of text

Line of text again

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And I have some simple code like this:

Code:

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#include <iostream>
#include <string>
using namespace std;
int main() {

        string line;

        while (getline(cin,line) )
                if (line == blank) cout << "A blank line!" << endl;

}

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What would I put in the "blank" spot to test if the line that was retrieved was blank? Thanks.

Code:

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if(str == '\n') {
 // it's a blank
 }

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I tried putting that in my code and I get a compile error. I then tried putting double quotes around it, but I received no output. Here's my code with the new addition:

Code:

---

#include <iostream>
#include <string>
using namespace std;
int main() {

        string line;

        while (getline(cin,line) )
                if (line == '\n') cout << "A blank line!" << endl;

}

---

Use double quotes around the \n. A std::string can't be compared to a single character.

I did that, but it doesn't seem to work. When it encounters the blank line, it should print "A blank line!" but instead it prints nothing at all. Is there something else that needs to be done?

On windows machines, a blank line is probably represented by "\r\n", not "\n".

But I'm running this program on UNIX. Sorry, I should have mentioned that before.

Quote:

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Originally Posted by Zildjian

But I'm running this program on UNIX. Sorry, I should have mentioned that before.

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Code:

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  if (str = "") {
      cout << "A blank line!" << endl;

  }

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Regards,

Dave

'\n' is the default delimiter for 'getline()' and any delimiter will be extracted but not stored. So probably check if the string is empty.

if (str == "") {

Quote:

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Originally Posted by Dave Evans

Code:

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  if (str == "") {
      cout << "A blank line!" << endl;

  }

---

Regards,

Dave

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fixed

Even better:

Code:

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if (line.empty())

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