Question

Have problem error in next obj-c code.

if (fabs(originalLocation.timestamp - ((CLLocation *)[lastLocations objectAtIndex:i]).timestamp) > constAverageLocationTimeout) 
{ 
    //do 
}

xCode sent err:

error: Semantic Issue: Arithmetic on pointer to interface 'NSDate', which is not a constant size in non-fragile ABI

Have any ideas?

Answer 1

your program (and the location of the compiler error) would make a lot more sense if you broke it up a little. perhaps something like:

NSDate * orginalDate = originalLocation.timestamp;
CLLocation * lastLocation = [lastLocations objectAtIndex:i];
NSDate * lastDate = lastLocation.timestamp;

NSTimeInterval originalTime = [originalDate timeIntervalSinceReferenceDate];
NSTimeInterval lastTime = [lastDate timeIntervalSinceReferenceDate];
NSTimeInterval elapsed = fabs(originalTime - lastTime);

if (elapsed > constAverageLocationTimeout) {
  /* do */
}

specifically, timestamp is a property of type NSDate, not a scalar number such as an NSTimeInterval.