title: .cpp file vanishes after compilation
body: <p>I can't explain how absolutely frustrating this will be if there is no way for me to recover this file. Honestly, I feel like there isn't, but I need to understand what the hell happened so I can take preventative steps in the future. Essentially, I am making a simple OOP Project involving fake bank accounts in EMACS, and during compilation, the .cpp file with all of my class code up and vanishes.</p>
  
  <p>Here are the terminal commands before and after the vanishing file:</p>
  
  <pre><code>    lin114-11:25% ls
      BankAccount.cpp  BankAccount.h  BankAccount.h~  main.cpp
      lin114-11:26% emacs &amp;
      [1] 23359
      lin114-11:27% g++ -o BankAccount.cpp main.cpp
      /tmp/ccEXMM25.o: In function `main':
      main.cpp:(.text+0x67): undefined reference to `CheckingAccount::driver()'
      main.cpp:(.text+0x78): undefined reference to `CheckingAccount::~CheckingAccount()'
      main.cpp:(.text+0xa1): undefined reference to `CheckingAccount::~CheckingAccount()'
      main.cpp:(.text+0xcc): undefined reference to `CheckingAccount::~CheckingAccount()'
      /tmp/ccEXMM25.o: In function `CheckingAccount::CheckingAccount(double, int,                                                                                        
      std::basic_string&lt;char, std::char_traits&lt;char&gt;, std::allocator&lt;char&gt; &gt;)':
      main.cpp:(.text._ZN15CheckingAccountC2EdiSs[_ZN15CheckingAccountC5EdiSs]+0x59):
      undefined reference to `vtable for CheckingAccount'
      collect2: ld returned 1 exit status
      lin114-11:28% ls
      BankAccount.h  BankAccount.h~  main.cpp
  </code></pre>
  
  <p>As you can see, BankAccount.cpp just up and disappears after compilation. What happened and is there anyway to recover the file?</p>