gistfile1.m

// iPhone OS programming circa 2008
// ================================

NSInteger fruitSorter(NSString *a, NSString *b, void *context) {
    return [a compare:b];
}

// ...

NSMutableArray *fruits = [[NSMutableArray alloc] initWithObjects:@"apple", @"pear", @"banana", nil];
[fruits sortUsingFunction:fruitSorter context:NULL];


// iOS programming circa 2013
// ==========================

NSMutableArray *fruits = @[@"apple", @"pear", @"banana"];
[fruits sortUsingComparator:^(NSString *a, NSString *b) { return [a compare:b]; }];


// iOS programming circa 2014
// ==========================

var fruits = ["apple", "pear", "banana"]
fruits.sort{ $0 < $1 }