Question

Hi all I have an enum type that holds my error codes.

The problem is that they are not sequential i.e.

enum{
    ErrorCode1                = 1,
    ErrorCode2                = 4,
    ErrorCode3                = 74
}; typedef NSInteger  MyErroCodes;

Also there are maybe 50 codes + so I really wouldn’t want to have to duplicate the data or do it manually, which is what I’ve seen so far in my searches. Any help would be greatly appreciated.

Answer 1

The enum construct only exists at compile time. At run time, your MyErrorCodes instances are plain integers, and the ErrorCodeN values are just plain integer constants. There is no way to extract metadata from your enum in runtime (well, maybe there is in the debug info etc, but you don’t want to go there…).

I suggest:

• Create a small script (Python, Perl or whatnot) to generate functions that map the numeric code to string values. In XCode, you can even run code generators during the compilation phase if you really want.
• Use metaprogramming or preprocessor macros to generate these functions during compilation. This requires some thought, but it can be done.