I am working with the following function atm, but I'm banging my head against a wall. 

```
-(double)fetchTimeUntilNextUpdateInSeconds{
    NSFetchRequest *fetchReq = [[NSFetchRequest alloc]initWithEntityName:@"DataInfo"];
    fetchReq.predicate = [NSPredicate predicateWithFormat:@"data_info_id == 1"];
    [fetchReq setPropertiesToFetch:[NSArray arrayWithObject:@"nextupdate"]];
    NSArray *array = [self.context executeFetchRequest:fetchReq error:nil];
    NSString *string = [[array valueForKey:@"nextupdate"] stringValue];
    NSLog(@"string: %@     array count:%lu", string, (unsigned long)array.count);
    NSArray *hoursAndMins = [string componentsSeparatedByString:@":"];
    int hours = [hoursAndMins[0] intValue];
    int mins = [hoursAndMins[1] intValue];

    return (mins*60)+(hours*60*60);
}

```

LOG: string: (
 "05:42"
) array count:1

I'm getting following error: `-[__NSArrayI componentsSeparatedByString:]: unrecognized selector sent to instance 0x174224060'`

fair enough, i try to invoke "stringValue" method on string (as showed in code snippet) and get the following instead:
`-[__NSArrayI stringValue:]: unrecognized selector sent to instance 0x174224060'`

The ladder makes me think I'm already receiving a string as `stringValue` is not a method of that class.... but why won't the first work then. Better yet, what am I doing wrong here?