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General Notes

It may not seem obvious, at least it wasn’t to me the first couple of days, but NSNumber does not support calculations directly. NSNumber is a class as opposed to a primitive datatype, so it does not replace the primitives like int, double, float, and the rest. This means that calculations done to them need to be converted from NSNumber to the appropriate primitive.

What is also important to note is that NSNumber is good for is storing numbers in NSArray, NSDictionary, NSSet, and the like (including their mutable siblings) because those classes only accept objects and not primitive datatypes. Even then, it is important to note there is a distinction between NSNumber and a “class” like NSInteger with the latter being a typedef to help manage 32-bit and 64-bit ints despite the NS prefix.

Generate random numbers within a specific range

There are dozens of ways this can be handled, but this is the simplest way I have come up with so far that is still safe from compiler errors, particularly the divide by zero errors.

- (int) randomInRangeMin:(int)min max:(int)max {
    // avoid any divide-by-zero-like errors
    if ( min == 0 && max == 0 ) {
        return 0;
    }
	return ( arc4random() % abs( max - min ) ) + min;
}