Simple stupid Pair in Objective-C

Pair.m

@interface Pair<FirstType, SecondType>: NSObject

@property FirstType first;
@property SecondType second;

+ (instancetype)pairWithFirst:(FirstType)first second:(SecondType)second;

@end

@implementation Pair

+ (instancetype)pairWithFirst:(id)first second:(id)second {
    __auto_type pair = [Pair new];
    pair.first = first;
    pair.second = second;
    return pair;
}

@end