NSMutableArray subclass init - objective-c

Question

I'm trying to make a function for a NSMutableArray subclass that only uses integer, but I don't want to use "count." How do I do this?
-(NSMutableArrayWithIntegers*)initWithCount:(NSInteger)count numbers:(NSInteger)firstInt, ...
{
self = [super init];
if (self) {
va_list args;
va_start(args, firstInt);
NSInteger arg = firstInt;
for (int i = 0; i < count; i++)
{
arg = va_arg(args, NSInteger);
[self addObject: [NSNumber numberWithInteger:arg]];
}
va_end(args);
}
return self;
}

Answer 1

I know this doesn't answer your question but it's important to let you know. Don't ever subclass NSMutableAnything. Use a category and thank me later:
#interface NSMutableArray (ListOfIntegers)
+(NSMutableArray)mutableArrayWithIntegers:(NSInteger)i, ... {
NSMutableArray *array = [[NSMutableArray alloc] initWithCapacity:whatever];
// do your thing
return array;
}
#end

Answer 2

First of all, the approach you currently have is just fine. Don't try getting rid of the count. There are alternatives, but they are only worse.
For example, you may use a sentinel value (which may not be inserted into the array) as the last argument, but in this case, you will have to make sure that you are not actually trying to insert this value to the array at all:
- (id)initWithIntegers:(NSInteger)first, ...
{
if (!(self = [super init])) return nil;
va_list args;
va_start(args, first);
NSInteger n;
if (first != NSIntegerMax) {
[self addObject:#(first)];
while ((n = va_arg(args, NSInteger)) != NSIntegerMax) {
[self addObject:#(n)];
}
}
va_end(args);
return self;
}
But really, this unnecessarily narrows the range of values that can be added - using that count argument is not a big deal.