Switching on objects

main.m

//
//  main.m
//

#import <Foundation/Foundation.h>
#import "NSObject+Switch.h"

int main(int argc, const char * argv[])
{
    @autoreleasepool {
        id str = @"Hello";
        [str switch:@{
            @"Hello": ^{
                NSLog(@"You said hello.");
            },
            @"Goodbye": ^{
                NSLog(@"You said goodbye.");
            }
        }
        default:^(id obj) {
            NSLog(@"No case matches for %@", obj);
        }];
    }
    return 0;
}

NSObject+Switch.h

//
//  NSObject+Switch.h
//

#import <Foundation/Foundation.h>

@interface NSObject (Switch)

- (void)switch:(NSDictionary *)cases default:(void (^)(id obj))defaultBlock;

@end

NSObject+Switch.m

//
//  NSObject+Switch.m
//

#import "NSObject+Switch.h"

@implementation NSObject (Switch)

- (void)switch:(NSDictionary *)cases default:(void (^)(id obj))defaultBlock
{
    void (^block)(id) = [cases objectForKey:self];
    if (block != NULL) {
        block(self);
    } else {
        defaultBlock(self);
    }
}

@end