运行这些命令：
create HelloWorld
cd HelloWorld
rake
错误：
libc++abi.dylib: terminating with uncaught exception of type NSException
================================================================================
The application terminated. A crash report file may have been generated by the
system, use rake crashlog'打开它。使用rake debug=1' to restart the app
in the debugger.
================================================================================
rake aborted!
TypeError: no implicit conversion from nil to integer
/Library/RubyMotion/lib/motion/project/template/ios.rb:243:in退出”
/Library/RubyMotion/lib/motion/project/template/ios.rb:243:in block in <top (required)>'