title: Receiving an "Error: expected an identifier" on C++ for "=="
body: <p>Im receiving an error on the " if (f_in); std::ifstream == int NULL);" code, where the "==" is underlines as the error and is saying "Error: expected as an identifier". I'm not sure on what to do and I am stuck :/. Here is the code:</p>
  
  <pre><code>#include &lt;iostream&gt;     // For cin/cout
  #include &lt;fstream&gt;      // For file stream objects (ifstream)
  #include &lt;string&gt;       // For the string data object
  
  using namespace std;
  
  int main()
  {
  
     ifstream f_in;   // Creat an object for an 'input' file stream
     string       data;   // An object to hold our data read in form the file
  
  
    )
  
  f_in.open("InputData.txt"); 
  
  if (f_in); std::ifstream == int NULL); {
      fprintf(stderr, "Can't open input file in.list!\n");
      exit(1);
  }
  
  
  f_in &gt;&gt; data;
  cout &lt;&lt; "First data item from file is: ' " &lt;&lt; data &lt;&lt; endl;
  
  f_in &gt;&gt; data;
  cout &lt;&lt; "Second data item from file is: ' " &lt;&lt; data &lt;&lt; endl;
  
  getline(f_in, data);
  cout &lt;&lt; "Line from file is: '" &lt;&lt; data &lt;&lt; endl;
  
  getline(f_in, data);
  cout &lt;&lt; "Next line from file is: '" &lt;&lt; data &lt;&lt; endl;
  
  // We are finished with the file. We need to close it.
  f_in.close();
  
  cout &lt;&lt; "Finished!\n";
  
  return 0;
  }
  </code></pre>