Generic HOM for NSArray

Each.h

#import <Foundation/Foundation.h>

@interface Each <Object> : NSObject

@property (nonatomic, strong) NSArray <Object> *array;

- (instancetype)initWithArray:(NSArray <Object> *)array;

@end


@interface NSArray <Object> (Each)

@property (nonatomic, readonly) Object each;

@end

Each.m

#import "Each.h"

@implementation Each

- (instancetype)initWithArray:(NSArray *)array {
  self = [super init];
  self.array = array;
  return self;
}

- (void)forwardInvocation:(NSInvocation *)invocation {
  [_array enumerateObjectsUsingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
    if ([obj respondsToSelector:[invocation selector]]) {
      [invocation invokeWithTarget:obj];
    }
  }];
}


- (NSMethodSignature *)methodSignatureForSelector:(SEL)aSelector {
  __block NSMethodSignature *sign;
  [_array enumerateObjectsUsingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
    if ([obj respondsToSelector:aSelector]) {
      sign = [obj methodSignatureForSelector:aSelector];
      *stop = YES;
    }
  }];
  return sign;
}

@end

@implementation NSArray (Each)

- (id)each {
  Each *each = [[Each alloc] initWithArray:self];
  return each;
}

@end