Example 1 of slow and fast NSDictionary access

slow_kvo_dictionary_example1.m

//
//  slow_kvo_dictionary_example.m
//
//  Created by Benedikt Terhechte on 07.12.11.
//  appventure.me
//

#import <Foundation/Foundation.h>

int main (int argc, const char * argv[])
{
  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
  NSDictionary *aDictionary = [NSDictionary dictionaryWithObject:
    [NSDictionary dictionaryWithObject:
      [NSDictionary dictionaryWithObject:
        [NSDictionary dictionaryWithObject: @"Zaphod Beeblebrox" forKey:@"friend"]
      forKey: @"data"]
     forKey: @"likes"]
    forKey: @"data"];
    
  // All benchmarks on a 2.7Ghy i7 MBP
  int i;
  for(i=0;i<5000000; i++) {
    // The slow & easy approach
    // Benchmark: 11.93 sec.
    [aDictionary valueForKeyPath:@"data.likes.data.friend"];
      
    // The fast but ugly and cumbersome approach
    // Benchmark: 1.53 sec.
    [[[[aDictionary objectForKey:@"data"] objectForKey:@"likes"] objectForKey: @"data"] objectForKey: @"friend"];      
  }
     
  [pool release];
  
  return 0;
}