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Ben Myhre
28,726 PointsHow can I avoid "Implicit conversion loses integer precision" warning following Treehouse steps?
I am in the midst of following the instructions, exactly, to extract a random picker from the controller to the models we are creating. I am getting a :
Implicit conversion loses integer precision: 'NSUInteger' (aka 'unsigned long') to 'u_int32_t' (aka 'unsigned int')
on the following code from the video on the line where random is set.
-(NSString*) randomPrediction {
int random = arc4random_uniform(self.predictions.count);
return [self.predictions objectAtIndex:random];
}
1 Answer
Stone Preston
42,016 Pointsthe reason this happens is that when on a 64 bit system the count variable of NSArray is a 64 bit integer, but arc4random_uniform expects a 32 bit integer as its argument.
to make the warning go away, just add a cast to an unsigned 32 bit integer to the predictions count:
-(NSString*) randomPrediction {
int random = arc4random_uniform((uint32_t) self.predictions.count);
return [self.predictions objectAtIndex:random];
}