Question

In Objective-C, are there any ways to indicate that an NSNumber* should actually be a BOOL? Right now my code looks like:

NSNumber *audio; // BOOL wrapper

Without the comment, it is not immediately obvious that *audio is a boolean value.

My first thought was to try

typedef NSNumber* BOOL;

but this gave a compiler error apparently because typedef doesn’t understand Objective-C.

Without changing the variable names (which is difficult when using existing APIs), how should I indicate that an NSNumber* holds a boolean value?

Answer 1

The code:

typedef NSNumber* BOOL;

doesn’t compile because BOOL is already a typedef, and it’s not allowed to redefine a typedef.

So you could use another name for that type, e.g.:

typedef NSNumber NSNumberBool;
NSNumberBool *audio;

Or, probably better, name the variable so that you know it is an NSNumber and contains a bool, this way you don’t even need to go look for the variable type:

NSNumber *audioNumberBool;
...
[audioNumberBool boolValue];