How to declare an enum value as being deprecated in ObjectiveC (2.0)

deprecated, enums, objective-c

Solution

I think you're attaching the `__attribute__` bit to the wrong side of the assignment operator. This seems to work fine:

typedef enum
{
   GeometricPoint,
   GeometricLine,
   GeometricRectangle,
   GeometricSquare __attribute__((deprecated)) = GeometricRectangle,
   GeometricCircle
}GeometricFigures;

and now assigning `GeometricSquare` gives a compiler warning:

int fig = GeometricSquare;    //'GeometricSquare' is deprecated

Problem

Suppose a long time ago, I had created the following enumeration: ``` typedef enum { GeometricPoint, GeometricLine, GeometricSquare, GeometricRectangle, GeometricCircle }GeometricFigures; ``` I introduced those a while ago within my awesome engine and now I have finally decided that people should not use `GeometricSquare` anymore as that is covered by `GeometricRectangle` already. For a start, I would possibly change my enumeration towards something like this: ``` typedef enum { GeometricPoint, GeometricLine, GeometricRectangle, GeometricSquare = GeometricRectangle, GeometricCircle }GeometricFigures; ``` That would certainly keep my awesome engine backwards compatible but on the other hand increase the legacy junk. Hence I would like to remove `GeometricSquare` altogether in a foreseeable future. To make that obvious to the users of my engine, I would like to mark `GeometricSquare` as being deprecated. My goal is that the documentation (doxygen) as well as the code completion (Xcode) and last but not least the compiler (GCC) will make it obvious to the user that `GeometricSquare` should not be used anymore and has been replaced by `GeometricRectangle`. For the documentation, I would simply use `@deprecated` keyword; ``` typedef enum { GeometricPoint, GeometricLine, GeometricRectangle, ///@deprecated Has been replaced by GeometricRectangle GeometricSquare = GeometricRectangle, GeometricCircle }GeometricFigures; ``` But how about Xcode and GCC? Unfortunately, the usual GCC (method) attribute does not seem to do the job. Adding `__attribute__((deprecated))` as drafted below causes a syntax error. ``` typedef enum { GeometricPoint, GeometricLine, GeometricRectangle, GeometricSquare = GeometricRectangle __attribute__((deprecated)), ``` Parse Issue Expected } ``` GeometricCircle }GeometricFigures; ``` So obviously that either does not work altogether or I am simply using it wrong.

Original source