Objective-Cで関数型プログラミングしたいなーと思ってやってみた。とりあえずFizzBuzz

main.m

#import <Foundation/Foundation.h>
#import "NSArray-Fanctional.h"

int main(int argc, const char * argv[])
{

    @autoreleasepool {
        
        [[[NSArray from:1 to:100] map:^(NSNumber *num){
            NSInteger i = [num longValue];
            return
                (i % 15 == 0)? @"FizzBuzz":
                (i % 3 == 0)? @"Fizz":
                (i % 5 == 0)? @"Buzz":
                [NSString stringWithFormat:@"%li",i];
        }]foreach:^(NSString *str){
            NSLog(@"%@",str);
        }];
        
    }
    return 0;
}

NSArray-Fanctional.h

#import <Foundation/Foundation.h>

typedef id (^fanc_t)(id);
typedef void (^noReturn_t)(id);

@interface NSArray (Fanctional)

+ (NSArray *)from:(NSInteger)from to:(NSInteger)to;

- (NSArray *)map:(fanc_t)fanc;
- (void)foreach:(noReturn_t)fanc;
@end

NSArray-Fanctional.m

#import "NSArray-Fanctional.h"

@implementation NSArray (Fanctional)

+ (NSArray *)from:(NSInteger)from to:(NSInteger)to
{
    NSMutableArray *array = [NSMutableArray array];
    for (NSInteger i = 0, _len = to - from + 1; i < _len; i++) {
        array[i] = [NSNumber numberWithLong:(from + i)];
    }
    return array;
}

- (NSArray *)map:(fanc_t)fanc
{
    NSMutableArray *array = [NSMutableArray array];
    for (NSInteger i = 0, _len = [self count]; i < _len; i++) {
        array[i] = fanc(self[i]);
    }
    return array;
}
- (void)foreach:(noReturn_t)fanc
{
    for (NSInteger i = 0, _len = [self count]; i < _len; i++) {
        fanc(self[i]);
    }
}
@end