title: IOS custom library functions should ignore if dependency framework are not available?
body: <p>I am building a library which has some functions which use <code>CoreTelephony</code> and <code>CoreLocation</code> library. These functions properly use @try-@catch. Now whoever includes this library has to include these framework in their application in order to use those functions. </p>
  
  <p>What I want: If the person doesn't include these frameworks, these functions should return nil as described below. However, it throws an error indicating necessity to include these frameworks.</p>
  
  <pre class="lang-c prettyprint-override"><code>+(NSString *)getLocation
  {
      @try {
          CLLocationManager *locationManager = [[CLLocationManager alloc] init];
  
          locationManager.delegate = self;
  
          locationManager.desiredAccuracy = kCLLocationAccuracyBest;
          locationManager.distanceFilter = kCLDistanceFilterNone;
          [locationManager startUpdatingLocation];
          [locationManager stopUpdatingLocation];
          CLLocation *location = [locationManager location];
          // Configure the new event with information from the location
  
          float longitude=location.coordinate.longitude;
          float latitude=location.coordinate.latitude;
  
          NSString *location_string=[[NSString alloc] initWithFormat:@"%d,%d",longitude,latitude];
  
          return location_string;
      }
     @catch (NSException *exception) 
     {
          return @"";
     }
     @finally 
     {
  
     }
  }
  </code></pre>