title: error in xcode : clang: error: linker command failed with exit code 1 (use -v to see invocation)
body: <p>getting the following error. 
  i did have duplicate names for a var but i have now changed these and the error is still there how can I fix this?</p>
  
  <pre><code>duplicate symbol _main in:
      /Users/James/Library/Developer/Xcode/DerivedData/project2_18094969-dbsiivorqvjflcejayyqrobtrdwt/Build/Intermediates/project2_18094969.build/Debug-iphonesimulator/project2_18094969.build/Objects-normal/x86_64/main.o
      /Users/James/Library/Developer/Xcode/DerivedData/project2_18094969-dbsiivorqvjflcejayyqrobtrdwt/Build/Intermediates/project2_18094969.build/Debug-iphonesimulator/project2_18094969.build/Objects-normal/x86_64/AppDelegate.o
  ld: 1 duplicate symbol for architecture x86_64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  </code></pre>