Class Not Declared?? (C++)
<blockquote>
  <p>ISBN.cpp:8: error: 'ISBN' has not been
  declared </p>
  
  <p>ISBN.cpp:8: error: ISO C++
  forbids declaration of 'ISBN' with no
  type ISBN.cpp: In function 'int
  ISBN()':</p>
  
  <p>ISBN.cpp:9: error: 'area' was
  not declared in this scope</p>
  
  <p>ISBN.cpp:10: error: 'publisher' was
  not declared in this scope</p>
  
  <p>ISBN.cpp:11: error: 'title' was not
  declared in this scope ISBN.cpp:12:
  error: 'checkdigit' was not declared
  in this scope ISBN.cpp:13: error:
  'isbnStr' was not declared in this
  scope</p>
</blockquote>

<p>Line 8 through 14 are:</p>

<pre><code>ISBN::ISBN() {
 area = NULL;
 publisher = NULL;
 title = NULL;
 checkdigit = NULL;
 isbnStr = NULL;
}
</code></pre>

<p>They are all declared in the header:</p>

<pre><code>class ISBNPrefix;
class ISBN
{
private:
 int area;
 int publisher;
 int title;
 char checkdigit;
 char* isbnStr[10];
public:
 ISBN();
...
</code></pre>

<p>Any ideas as to what could be the issue here? I'm guessing that its something simple I'm missing.</p>
