Functional Objective-C NSArray

NSArray+Functional.h

//
//  NSArray+Functional.h
//  DynamicFeatures
//
//  Created by Leandro Silva on 4/10/10.
//  Copyright 2010 __MyCompanyName__. All rights reserved.
//

#import <Cocoa/Cocoa.h>


@interface NSArray (Functional)

- (void) each: (void (^)(id item))block;
- (NSArray *) map: (id (^)(id obj))block;
- (NSArray *) select: (BOOL (^)(id obj))block;

@end

NSArray+Functional.m

//
//  NSArray+Functional.m
//  DynamicFeatures
//
//  Created by Leandro Silva on 4/10/10.
//  Copyright 2010 __MyCompanyName__. All rights reserved.
//

#import "NSArray+Functional.h"


@implementation NSArray (Functional)

- (void) each: (void (^)(id item))block
{
	for (id *object in self) {
		block(object);
	}
}

- (NSArray *) map: (id (^)(id obj))block
{
    NSMutableArray *new = [NSMutableArray array];
    
    for (id obj in self) {
        id newObj = block(obj);
        [new addObject: newObj ? newObj : [NSNull null]];
    }
    
    return new;
}

- (NSArray *) select: (BOOL (^)(id obj))block
{
    NSMutableArray *new = [NSMutableArray array];
    
    for (id obj in self) {
        if (block(obj)) {
            [new addObject: obj];
        }
    }
    
    return new;
}

@end