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Debugging

Once a product has been designed and an initial version built, you spend time testing it, to find and correct bugs. Xcode contains a full-featured source-level debugger that lets you step through your code line by line, set breakpoints, and view variables, stack frames, and threads. The following chapters introduce executable environments, and show you how to use them to run your program under different conditions from within Xcode. They also describe Xcode’s graphical debugger, and how to use it to examine program data and control execution of your code; as well as how to use Fix and Continue to make changes to your source code and continue debugging.

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