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ioscocoalumberjack

What can be the cause of "use of undeclared identifier LOG_LEVEL_VERBOSE" message

I'm trying to configure cocoalumberjack and when I've added ddLogLevel set to LOG_LEVEL_VERBOSE XCode throws "use of undeclared identifier" error. Why is that? How to avoid?

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Solution

  • This question indicates that clearing DerivedData and restarting Xcode solves this kind of error.

    However you should not include variables in the pre-compiled header as it will be included in every source file and prefix files are somewhat complicated compared to normal header files.

    Better is to have use a Constants.h file which contains:

    extern int ddLogLevel;

    and #import that into your prefix file.

    Then create an Constants.m with:

    int ddLogLevel =
#ifdef DEBUG
                 LOG_LEVEL_VERBOSE;
#else
                 LOG_LEVEL_ERROR;
#endif

    This way there is only one instance of ddLogLevel and it can be easily changed at runtime if necessary.

    See this question for hints about prefix file best practices.