{"id":697,"date":"2017-01-13T17:08:26","date_gmt":"2017-01-13T08:08:26","guid":{"rendered":"http:\/\/www.uturtle.com\/blog\/?p=697"},"modified":"2017-01-13T17:08:27","modified_gmt":"2017-01-13T08:08:27","slug":"%eb%b2%88%ec%97%ad-nullability%ec%99%80-generics%eb%a1%9c-objective-c%ec%9d%98-%ec%bd%94%eb%93%9c%eb%a5%bc-swift%ec%97%90%ec%84%9c-%ec%93%b0%ea%b8%b0-%ec%89%bd%ea%b2%8c-%ed%95%b4%eb%b3%b4%ec%9e%90","status":"publish","type":"post","link":"https:\/\/www.jinukbaek.com\/blog\/ko\/archives\/697","title":{"rendered":"[\ubc88\uc5ed] Nullability\uc640 Generics\ub85c Objective-C\uc758 \ucf54\ub4dc\ub97c Swift\uc5d0\uc11c \uc4f0\uae30 \uc27d\uac8c \ud574\ubcf4\uc790"},"content":{"rendered":"

\uc774 \uae00\uc740 qiita\uc5d0 \uc791\uc131\ub41c http:\/\/qiita.com\/motokiee\/items\/b30514204a819a09425b<\/a>(\uc791\uc131\uc790 motokiee\ub2d8, 2016-02-29 \ud22c\uace0)\uc744 \ubc88\uc5ed\ud55c \uae00\uc785\ub2c8\ub2e4.<\/p><\/blockquote>\n

Objective-C\uc5d0\uc11c Swift\ub85c \uc774\uc804\ud558\ub294 \uacfc\ub3c4\uae30<\/h1>\n

\uc218\ub144\uac04 \uac1c\ubc1c\ub418\uc5b4\uc628 \uc571\uc5d0 \uc2ac\uc2ac Swift\ub97c \ub3c4\uc785\ud558\uae30 \uc2dc\uc791\ud558\uc9c0 \uc54a\uc558\ub098\uc694? \ub2f9\uc5f0\ud788 Objective-C\uc5d0\uc11c \ub9cc\ub4e4\uc5b4\uc9c4 \uc7ac\uc0b0\uc744 \uadf8\ub300\ub85c \ub454 \uc0c1\ud0dc\ub85c \uac1c\ubc1c\ud558\uac8c \ub420 \uac83\uc774\ub77c\uace0 \uc0dd\uac01\ud569\ub2c8\ub2e4.<\/p>\n

\uc774 \ub54c Optional\uc744 \ub2e4\ub8e8\ub294 \uac83\uc5d0 \ub300\ud574 \uace4\ub780\ud574\ud558\uace0\uc788\uc9c0 \uc54a\uc744\uae4c \uc0dd\uac01\uc774 \ub4ed\ub2c8\ub2e4. Objective-C\uc5d0\uc11c\ub294 \ub9ac\uc2dc\ubc84\uac00 nil<\/code>\uc778 \uc0c1\ud0dc\ub85c \uba54\uc2dc\uc9c0\ub97c \ubcf4\ub0b4\ub354\ub77c\ub3c4 \ud06c\ub798\uc2dc\uac00 \ubc1c\ud558\uc9c0 \uc54a\uc558\uc9c0\ub9cc, Optional\uc774 \uc788\ub294 Swift\ub85c \ubd80\ud130 Objective-C\uc758 \ucf54\ub4dc\ub97c \ud638\ucd9c\ud558\ub294 \uacbd\uc6b0\uc5d0\ub294 \uc880 \uace4\ub780\ud574 \uc9d1\ub2c8\ub2e4.<\/p>\n

Swift\uc640 Objective-C\uc758 \ud638\ud658\uc131\uc744 \uac15\ud654\ud558\uae30 \uc704\ud574\uc11c nullable<\/code>, nonnull<\/code>\uc774 Objective-C\uc5d0 \ucd94\uac00\ub418\uc5c8\uc2b5\ub2c8\ub2e4.<\/p>\n

Swift\uc758 \ucf54\ub4dc\ub97c \uc791\uc131\ud560 \ub54c, \uc774\ub7ec\ud55c \ud615\uc218\uc2dd\uc790(Type qualifier)\ub97c \uc0ac\uc6a9\ud574\uc11c Objective-C \ucabd\ub3c4 \uac1c\uc120\ud558\uc5ec Swift \ub3c4\uc785\uc744 \uc880 \ub354 \uc27d\uac8c \ud560 \uc218 \uc788\uc744 \uac83\uc774\ub77c\uace0 \uc0dd\uac01\ud569\ub2c8\ub2e4.<\/p>\n

nullable<\/code><\/h2>\n

nullable<\/code>\uc740 Optional\uc5d0 \uc788\ub294 nil<\/code>\uc744 \ud5c8\uc6a9\ud55c\ub2e4\ub294 \uac83\uc744 \uba85\uc2dc\ud558\uae30 \uc704\ud55c \ud615\uc218\uc2dd\uc790\uc785\ub2c8\ub2e4.<\/p>\n

\uc608\ub97c \ub4e4\uba74, NSData<\/code>\uc758 initWithContentsOfURL:<\/code> \uc774\ub2c8\uc15c\ub77c\uc774\uc838\ub294 \uc544\ub798\uc640 \uac19\uc774 \uc815\uc758\ub418\uc5b4 \uc788\uc5b4\uc11c \ub9ac\ud134\uac12\uc774 nil<\/code>\uc774 \ub420 \uc218\uc788\ub2e4\ub294 \uac83\uc744 \uba85\uc2dc\ud558\uace0 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n

- (nullable instancetype)initWithContentsOfURL:(NSURL *)url;\r\n<\/code><\/pre>\n
\uc774\uac83\uc744 \uc2a4\uc704\ud504\ud2b8\uc5d0\uc11c \ubcf4\uba74 \uc544\ub798\uc640 \uac19\uc774 failable initializer\ub85c \ubcc0\ud658\ub418\uc5b4 \uc2e4\ud328\ud560 \uac00\ub2a5\uc131\uc774 \uc788\ub294 \uc774\ub2c8\uc15c\ub77c\uc774\uc838\uac00 \ub418\ub294 \uac83\uc744 \uc54c \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
public init?(contentsOfURL url: NSURL)\r\n<\/code><\/pre>\n
\uc774\uc640 \uac19\uc774 \uc778\uc2a4\ud134\uc2a4 \uc0dd\uc131\uc774\ub791 \ud30c\ub77c\ubbf8\ud130, \ub9ac\ud134\uac12\uc774 nil<\/code>\uc774 \ub420 \uc218 \uc788\ub294 \uacbd\uc6b0\uc5d0\ub294 Objective-C\ucabd\uc5d0 nullable<\/code>\uc744 \uc9c0\uc815\ud574 \ub450\ub294 \uac83\uc73c\ub85c Swift\uc5d0\uc11c Optional\uc73c\ub85c \ub2e4\ub8e8\ub294 \uac83\uc774 \uac00\ub2a5\ud574\uc9d1\ub2c8\ub2e4.<\/p>\n
Objective-C\uc5d0\uc11c\ub294 nullable<\/code>\uc744 \uc9c0\uc815\ud558\uc9c0 \uc54a\ub294 \uacbd\uc6b0\uc5d0\ub294 “Implicitly unwrapped optional”\uc774 \ub429\ub2c8\ub2e4. \uc544\ub798\uc640 \uac19\uc740 Objective-C\uc758 \uba54\uc18c\ub4dc\uc5d0\uc11c \uace0\ub824\ud574\ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n
- (UIImage*)createImage;\r\n<\/code><\/pre>\n
nullable<\/code>\uc744 \ubd99\uc774\uc9c0 \uc54a\uace0 Swift\uc5d0\uc11c \uc0ac\uc6a9\ud558\ub824\uace0 \ud558\uba74 \ubcc0\ud658\uc2dc\uc5d0 “Implicitly unwrapped optional”\uc774 \ub418\uc5b4 \ubc84\ub9bd\ub2c8\ub2e4.<\/p>\n
func createImage() -> UIImage!\r\n<\/code><\/pre>\n
\uc774 \uba54\uc18c\ub4dc\uc758 \ub9ac\ud134 \uac12\uc744 \uc0ac\uc6a9\ud558\ub824\uace0 \ud560 \ub54c nil<\/code>\uc77c \uacbd\uc6b0 \ud06c\ub798\uc2dc\uac00 \ubc1c\uc0dd\ud574\ubc84\ub824\uc11c Swift\ubd80\ud130 \uc774 Objective-C\uc758 \ucf54\ub4dc\ub97c \uc0ac\uc6a9\ud560 \ub54c\uc5d0 \ubd88\uc548\ud55c \ubd80\ubd84\uc774 \ub530\ub77c\ub2e4\ub2c8\uac8c \ub429\ub2c8\ub2e4. \ud639\uc2dc \uc774\ub7ec\ud55c \ucc98\ub9ac\ub97c \ubcf4\uac8c \ub41c\ub2e4\uba74 nullable<\/code>\uc744 \uc9c0\uc815\ud558\uc5ec Swift\ucabd\uc5d0\uc11c Optional\uc73c\ub85c \uc774\uc6a9\uac00\ub2a5\ud558\ub3c4\ub85d \ud558\uba74 Swift\uc5d0\uc11c\ub3c4 \uc548\uc2ec\ud558\uace0 \uc774\uc6a9\ud560 \uc218 \uc788\uac8c \ub429\ub2c8\ub2e4.<\/p>\n
- (nullable UIImage*)createImage;\r\n<\/code><\/pre>\n
\uc544\ub798\uc758 Objective-C\uc758 \ucf54\ub4dc\ub97c \uc218\uc815\ud558\uba74 Swift\uc5d0\uc11c\ub294<\/p>\n
func createImage() -> UIImage?\r\n<\/code><\/pre>\n
\uacfc \uac19\uc774 \ubcc0\ud658\ub429\ub2c8\ub2e4.<\/p>\n
nonnull<\/code><\/h2>\n
nonnull<\/code>\uc740 Optional\uc774 \uc544\ub2c8\ub77c\ub294 \uac83\uc744 \uba85\uc2dc\ud558\uae30 \uc704\ud55c \ud615\uc218\uc2dd\uc790\ub85c nonnull<\/code>\uc744 \ud568\uc218\ub791 \uba54\uc18c\ub4dc\uc758 \ud30c\ub77c\ubbf8\ud130, \ub9ac\ud134 \uac12\uc5d0 \uc9c0\uc815\ud558\ub294 \uacbd\uc6b0\uc5d0\ub294 Optional\ud55c \ubcc0\uc218\ub97c \uc9c0\uc815\ud558\ub294 \uac83\uc774 \ubd88\uac00\ub2a5\ud574\uc9d1\ub2c8\ub2e4.<\/p>\n
NS_ASSUME_NONNULL_BEGIN<\/code>, NS_ASSUME_NONNULL_END<\/code><\/h3>\n
\ud558\uc9c0\ub9cc UIKit\uc758 \uc18c\uc2a4\ucf54\ub4dc\ub97c \ud655\uc778\ud574\ubcf4\uba74 nonnull<\/code>\uc744 \ucc3e\uc744 \uc218 \uc5c6\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc608\ub97c \ub4e4\uba74 UIVisualEffectView<\/code>\ub294 \uc774\ud558\uc640 \uac19\uc774 \uc815\uc758 \ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4\ub9cc nonnull<\/code>\uc740 \uc5b4\ub514\uc5d0\ub3c4 \uc4f0\uc774\uace0 \uc788\uc9c0 \uc54a\uc2b5\ub2c8\ub2e4. nullable<\/code>\uc740 \uc81c\ub300\ub85c \uc4f0\uc774\uace0 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
NS_CLASS_AVAILABLE_IOS(8_0) @interface UIVisualEffectView : UIView <NSSecureCoding>\r\n@property (nonatomic, strong, readonly) UIView *contentView; \/\/ Do not add subviews directly to UIVisualEffectView, use this view instead.\r\n@property (nonatomic, copy, nullable) UIVisualEffect *effect;\r\n- (instancetype)initWithEffect:(nullable UIVisualEffect *)effect NS_DESIGNATED_INITIALIZER;\r\n- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;\r\n@end\r\n<\/code><\/pre>\n
\ud558\uc9c0\ub9cc Swift\uc758 \ubcc0\ud658\uc740 \uc81c\ub300\ub85c Optional\uc774 \uc544\ub2c8\ub3c4\ub85d \ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
@available(iOS 8.0, *)\r\npublic class UIVisualEffectView : UIView, NSSecureCoding {\r\n    public var contentView: UIView { get } \/\/ Do not add subviews directly to UIVisualEffectView, use this view instead.\r\n    @NSCopying public var effect: UIVisualEffect?\r\n    public init(effect: UIVisualEffect?)\r\n    public init?(coder aDecoder: NSCoder)\r\n}\r\n<\/code><\/pre>\n
\uc989 nonnull<\/code>\uc758 \uc9c0\uc815\uc740 \uc81c\ub300\ub85c \ub418\uc5b4 \uc788\ub2e4\ub294 \uac83\uc785\ub2c8\ub2e4. \uc65c nonnull<\/code>\uc774 \uc9c0\uc815\ub418\uc9c0 \uc54a\uc740\uac83\uacfc \uc0c1\uad00\uc5c6\uc774 \ubcc0\ud658\uc774 \uac00\ub2a5\ud55c \uac78\uae4c\uc694?<\/p>\n
\uc54c\uc544\ubcf4\ub2c8 NS_ASSUME_NONNULL_BEGIN<\/code>\uacfc NS_ASSUME_NONNULL_END<\/code> \ub9e4\ud06c\ub85c\uac00 \uc0ac\uc6a9\ub418\uc5b4 \uc788\uc5c8\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc55e\uc5d0\uc11c \uc774\uc57c\uae30 \ud588\ub358 UIVisualEffectView.h\uc5d0\ub3c4 \uc81c\ub300\ub85c \uc774 \ub9e4\ud06c\ub85c\uac00 \uc0ac\uc6a9\ub418\uc5b4 \uc788\uc5c8\uc2b5\ub2c8\ub2e4.<\/p>\n
\/\/\r\n\/\/  UIVisualEffectView.h\r\n\/\/  UIKit\r\n\/\/\r\n\/\/  Copyright (c) 2014-2015 Apple Inc. All rights reserved.\r\n\/\/\r\n\r\n#import <UIKit\/UIKit.h>\r\n\r\nNS_ASSUME_NONNULL_BEGIN\r\n\r\n\/\/ ...\uc911\ub7b5\r\n\r\nNS_CLASS_AVAILABLE_IOS(8_0) @interface UIVisualEffectView : UIView <NSSecureCoding>\r\n@property (nonatomic, strong, readonly) UIView *contentView; \/\/ Do not add subviews directly to UIVisualEffectView, use this view instead.\r\n@property (nonatomic, copy, nullable) UIVisualEffect *effect;\r\n- (instancetype)initWithEffect:(nullable UIVisualEffect *)effect NS_DESIGNATED_INITIALIZER;\r\n- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder NS_DESIGNATED_INITIALIZER;\r\n@end\r\n\r\nNS_ASSUME_NONNULL_END\r\n<\/code><\/pre>\n
Foundation\uacfc UIKit\uc758 \uc18c\uc2a4\ub97c \ucc3e\uc544\ubcf4\uba74 \uc774 \ub9e4\ud06c\ub85c\uac00 \uc0ac\uc6a9\ub418\uc5b4 \uc788\uc5c8\uc2b5\ub2c8\ub2e4.<\/p>\n
\ud655\uc2e4\ud788 nonnull<\/code>, nullable<\/code>\uc744 \ud558\ub098\ud558\ub098 \ub2e4 \uc4f0\uace0 \uc788\ub294 \uac83\uc740 \ud070\uc77c\uc774\uaca0\uc9c0\uc694. Objective-C\uc5d0\uc11c nonnull<\/code>, nullable<\/code>\uc744 \ubd99\uc77c \ud544\uc694\uac00 \uc788\ub294 \uacbd\uc6b0\ub294 \uc801\uadf9\uc801\uc73c\ub85c NSASSUME_NONNULL_BEGIN<\/code>\uacfc NS_ASSUME_NONNULL_END<\/code>\uc744 \uc0ac\uc6a9\ud558\uace0 nullable<\/code>\ub9cc\uc744 \uc4f0\ub294 \uac83\uc774 \uc88b\uc744\uc9c0\ub3c4 \ubaa8\ub974\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc8fc\uc758<\/h3>\n
\uac19\uc740 \ud30c\uc77c\ub0b4\uc5d0 \uba54\uc18c\ub4dc\uc640 \ud504\ub85c\ud37c\ud2f0\uc5d0 \ud558\ub098\ub77c\ub3c4 nonnull<\/code>, nullable<\/code>\uc744 \uc4f0\ub294 \uacbd\uc6b0, \ud30c\uc77c \ub0b4\uc758 \ubcf4\ub4e0 \uba54\uc18c\ub4dc\uc758 \ud30c\ub77c\ubbf8\ud130, \ub9ac\ud134 \uac12, \ud504\ub85c\ud37c\ud2f0\uc5d0 \ud615\uc218\uc2dd\uc790\ub97c \ubd99\uc774\uc9c0 \uc54a\uc73c\uba74 \uc548\ub429\ub2c8\ub2e4. warning\uc774 \ubc1c\uc0dd\ud569\ub2c8\ub2e4.<\/p>\n
\"\"<\/a><\/p>\n
 <\/p>\n
Lightweight Generics<\/h2>\n
Swift\ub85c\ubd80\ud130 Objective-C\uc758 \ucf54\ub4dc\ub97c \uc0ac\uc6a9\ud558\ub824\uace0 \ud558\ub294 \ub54c, NSArray\ub85c\ubd80\ud130 \ubcc0\ud658\uacfc NSDictionary\ub85c\ubd80\ud130 Dictionary\uc758 \ubcc0\ud658\uc5d0\uc11c\ub294 \uace4\ub780\ud560 \ubd80\ubd84\uc774 \uc5c6\uc2b5\ub2c8\ub2e4\ub9cc \ubc30\uc5f4 \uc694\uc18c\uc758 \ud615\uc774 AnyObject\uac00 \ub418\uc5b4\ubc84\ub824 \uace4\ub780\ud574 \uc9c8 \uc218 \uc788\uc744 \uac83\uc774\ub77c \uc0dd\uac01\ud569\ub2c8\ub2e4.<\/p>\n
\uc774\uc640 \uac19\uc740 \uacbd\uc6b0\uc5d0 guard<\/code>\ub791 Optional Binding\uac19\uc740 \uac83\uc744 \uc0ac\uc6a9\ud574\uc11c \uc548\uc804\ud558\uac8c \ud615\ubcc0\ud658\ud558\uc5ec \uad6c\ud604\ud560 \uac83\uc774\ub77c \uc0dd\uac01\ud558\uc9c0\ub9cc Objective-C\uc758 \ucf54\ub4dc\ub97c Generics\ub97c \uc0ac\uc6a9\ud574\uc11c \uc218\uc815\ud558\ub294 \ud3b8\uc774 \ub354 \uc88b\uc544\ubcf4\uc785\ub2c8\ub2e4.<\/p>\n
UIView\ub294 subviews<\/code>\ub77c \ubd88\ub9ac\uc6b0\ub294 NSArray<\/code>\uc758 \ud504\ub85c\ud37c\ud2f0\ub97c \uac00\uc9c0\uace0 \uc788\uc2b5\ub2c8\ub2e4\ub9cc, Generics\ub97c \uc0ac\uc6a9\ud574\uc11c UIView<\/code>\uc758 \ubc30\uc5f4\uc774\ub77c\ub294 \uac83\uc744 \uba85\uc2dc\ud558\uace0 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
@property(nonatomic,readonly,copy) NSArray<__kindof UIView *> *subviews;\r\n<\/code><\/pre>\n
__kindof<\/code>\ub294 \uc11c\ube0c\ud074\ub798\uc2a4(\uc790\uc2dd \ud074\ub798\uc2a4)\ub3c4 \ud5c8\uc6a9\ud558\uae30 \uc704\ud55c \uc5b4\ub178\ud14c\uc774\uc158\uc785\ub2c8\ub2e4. subviews<\/code>\ub294 UIView\uc758 \uc11c\ube0c\ud074\ub798\uc2a4\ub3c4 \ud5c8\uc6a9\ud558\ub294 \uac83\uc744 \uba85\uc2dc\ud569\ub2c8\ub2e4.<\/p>\n
Objective-C\uc5d0 Nullability\uc640 Generics\uc744 \uc9c0\uc815\ud574 \uac00\ub294 \uacf5\uc815<\/h2>\n
Objective-C\uc5d0\uc11c \uc774\ud558\uc640 \uac19\uc774 \uc815\uc758\ub418\uc5b4\uc788\ub294 \uc624\ube0c\uc81d\ud2b8\ub97c \ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n
@interface MNPerson : NSObject\r\n@property (nonatomic, copy) NSString *name;\r\n@property (nonatomic) NSUInteger age;\r\n@property (nonatomic, copy) NSArray *items;\r\n- (NSString*)hey;\r\n- (instancetype)initWithName:(NSString*)name age:(NSUInteger)age;\r\n@end\r\n<\/code><\/pre>\n
\uc774\uac83\uc744 Swift\ub85c\ubd80\ud130\ub3c4 \uc0ac\uc6a9\ud558\uae30 \uc27d\ub3c4\ub85d Nullability\uc640 Generics\ub97c \uc9c0\uc815\ud574\ubcf4\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc544\ubb34 \uc190\ub3c4 \ub300\uc9c0 \uc54a\uc740 \uacbd\uc6b0, Swift\uc5d0\uc11c\ub294 \uc774\ub807\uac8c \ubcf4\uc785\ub2c8\ub2e4. \uc774\ub2c8\uc15c\ub77c\uc774\uc838\uc640 \ud504\ub85c\ud37c\ud2f0\uc5d0 !<\/code>\uac00 \ubd99\uc5b4\uc11c “Implicitly unwrapped optional”\uc774 \ub41c \uac83\uc744 \uc54c \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
public class MNPerson : NSObject {\r\n    public var name: String!\r\n    public var age: UInt\r\n    public var items: [AnyObject]!\r\n    public func hey() -> String!\r\n    public init!(name: String!, age: UInt)\r\n}\r\n<\/code><\/pre>\n
Objective-C\uc758 \ud5e4\ub354\uac00 Swift\uc5d0\uc11c \uc5b4\ub5a4\uc2dd\uc73c\ub85c \ud45c\uc2dc\ub418\ub294\uc9c0\ub97c \ud655\uc778\ud558\ub294 \ubc29\ubc95<\/h3>\n
Objective-C\uc5d0\uc11c Nullability\uc640 Generics\ub97c \uc9c0\uc815\ud560 \ub54c, jump bar\uc758 \uc88c\uce21 \ub05d\uc5d0 \uc788\ub294 \ubc84\ud2bc\uc744 \ud074\ub9ad\ud558\uba74 \ub098\ud0c0\ub098\ub294 “Generated Interface”\ub97c \uc0ac\uc6a9\ud574\uc11c Objective-C\uc758 \ud5e4\ub354\ud30c\uc77c\uc774 Swift\uc5d0 \uc5b4\ub5a4 \uc778\ud130\ud398\uc774\uc2a4\uac00 \ub418\ub294\uc9c0 \ud655\uc778\ud558\ub294 \uac83\uc774 \uac00\ub2a5\ud569\ub2c8\ub2e4.<\/p>\n
\"\"<\/a><\/p>\n
 <\/p>\n
nullable<\/code>\uc758 \uc124\uc815<\/h3>\n
\uba3c\uc800 nullable<\/code>\uc744 \ubd99\uc5ec\ubcf4\ub3c4\ub85d \ud569\uc2dc\ub2e4. \uc544\ub798\uc640 \uac19\uc774 \ub429\ub2c8\ub2e4.<\/p>\n
@interface MNPerson : NSObject\r\n@property (nullable, nonatomic, copy) NSString *name;\r\n@property (nonatomic) NSUInteger age;\r\n@property (nullable, nonatomic, copy) NSArray *items;\r\n- (nullable NSString*)hey;\r\n- (nullable instancetype)initWithName:(nullable NSString*)name age:(NSUInteger)age;\r\n@end\r\n<\/code><\/pre>\n
Nullability\ub294 \ud3ec\uc778\ud130\ud615\ub9cc \uc9c0\uc815\ud558\ub294 \uac83\uc774\ubbc0\ub85c primitive\ud55c \uac12, NSUInteger<\/code>\uac19\uc740 \uac83\uc5d0\ub294 nullable<\/code>\uc744 \ubd99\uc77c \ud544\uc694\uac00 \uc5c6\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc774\uac83\uc744 Generated Interface\uc5d0\uc11c \ubcf4\uba74 \uc544\ub798\uc640 \uac19\uc774 \ub429\ub2c8\ub2e4.<\/p>\n
public class MNPerson : NSObject {\r\n    public var name: String?\r\n    public var age: UInt\r\n    public var items: [AnyObject]?\r\n    public func hey() -> String?\r\n    public init?(name: String?, age: UInt)\r\n}\r\n<\/code><\/pre>\n
nonnull<\/code>\uc758 \uc124\uc815<\/h3>\n
\uc6b0\uc120 Optional\uc73c\ub85c \ucde8\uae09\ub418\uace0 \uc788\ub3c4\ub85d \ub418\uc5c8\uc2b5\ub2c8\ub2e4. \ud558\uc9c0\ub9cc \ubaa8\ub4e0 \uac83\uc774 Optional\uc774\ub77c\uba74 \ud558\ub098\ud558\ub098 Optional Binding\uc73c\ub85c \uac12\uc744 \ub044\uc9d1\uc5b4\ub0b4\uc9c0 \uc54a\uc73c\uba74 \uc548\ub418\uae30 \ub54c\ubb38\uc5d0 \uc880 \uadc0\ucc2e\uc2b5\ub2c8\ub2e4.<\/p>\n
nonnull<\/code>\uc73c\ub85c \ucde8\uae09\ud558\ub294 \uc7a5\uc18c\uac00 \uc5c6\ub098 \uad6c\ud604\uc744 \ud655\uc778\ud574\ubd05\uc2dc\ub2e4.<\/p>\n
- (instancetype)initWithName:(NSString*)name age:(NSUInteger)age {\r\n    self = [super init];\r\n\r\n    if (self) {\r\n        _name = name;\r\n        _age = age;\r\n    }\r\n    return self;\r\n}\r\n\r\n\r\n- (NSString*)hey {\r\n    return @\"hey\";\r\n}\r\n<\/code><\/pre>\n
\uc774\ub2c8\uc15c\ub77c\uc774\uc838\uc5d0\uc11c \uc778\uc2a4\ud134\uc2a4 \ubcc0\uc218\uc778 _name<\/code>\uacfc _age<\/code>\uc5d0 \uac12\uc774 \uc124\uc815\ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4. hey<\/code> \uba54\uc18c\ub4dc\ub3c4 \uc2e4\ud328 \uac00\ub2a5\uc131\uc740 \uc5c6\uae30 \ub54c\ubb38\uc5d0 \uc5ec\uae30\uc5d0 \ud574\ub2f9\ud558\ub294 \ud504\ub85c\ud37c\ud2f0\ub791 \uba54\uc18c\ub4dc\uc758 \ud30c\ub77c\ubbf8\ud130\ub97c nonnull<\/code>\uc73c\ub85c \ud574\ubd05\uc2dc\ub2e4.<\/p>\n
@interface MNPerson : NSObject\r\n@property (nonnull, nonatomic, copy) NSString *name;\r\n@property (nonatomic) NSUInteger age;\r\n@property (nullable, nonatomic, copy) NSArray *items;\r\n- (nonnull NSString*)hey;\r\n- (nonnull instancetype)initWithName:(nonnull NSString*)name age:(NSUInteger)age;\r\n@end\r\n<\/code><\/pre>\n
Swift\uc5d0\uc11c \ubd10\ubcf4\uba74 \uc774\ub807\uac8c \ub429\ub2c8\ub2e4.<\/p>\n
public class MNPerson : NSObject {\r\n    public var name: String\r\n    public var age: UInt\r\n    public var items: [AnyObject]?\r\n    public func hey() -> String?\r\n    public init(name: String, age: UInt)\r\n<\/code><\/pre>\n
NS_ASSUME_NONNULL_BEGIN<\/code>,NS_ASSUME_NONNULL_END<\/code> \ub9e4\ud06c\ub85c\ub97c \uc0ac\uc6a9\ud558\uba74 \uc544\ub798\uc640 \uac19\uc774 \uc4f8 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
NS_ASSUME_NONNULL_BEGIN\r\n\r\n@interface MNPerson : NSObject\r\n@property (nonatomic, copy) NSString *name;\r\n@property (nonatomic) NSUInteger age;\r\n@property (nullable, nonatomic, copy) NSArray *items;\r\n- (NSString*)hey;\r\n- (instancetype)initWithName:(NSString*)name age:(NSUInteger)age;\r\n@end\r\nNS_ASSUME_NONNULL_END\r\n<\/code><\/pre>\n
nil<\/code>\uc774 \ub420 \uac00\ub2a5\uc131\uc774 \uc788\ub294 \uacf3\uc5d0\ub9cc nullable<\/code>\uc744 \uc9c0\uc815\ud560 \ud544\uc694\uac00 \uc788\uc2b5\ub2c8\ub2e4\ub9cc nonnull<\/code>\uc778 \ud504\ub85c\ud37c\ud2f0\uc5d0 \ub300\ud558\uc5ec\ub294 \uc9c0\uc815\uc774 \ubd88\ud544\uc694\ud574\uc9d1\ub2c8\ub2e4.<\/p>\n
\uacb0\uacfc\ub294 \uc55e\uacfc \uac19\uc740 \ud615\ud0dc, \uc544\ub798\uc640 \uac19\uc774 \ub429\ub2c8\ub2e4.<\/p>\n
public class MNPerson : NSObject {\r\n    public var name: String\r\n    public var age: UInt\r\n    public var items: [AnyObject]?\r\n    public func hey() -> String\r\n    public init(name: String, age: UInt)\r\n}\r\n<\/code><\/pre>\n
Generics\uc758 \uc124\uc815<\/h3>\n
\uc774\uac83\uc73c\ub85c Optional\uc758 \uc124\uc815\uc740 \uc644\ub8cc\ud588\uc2b5\ub2c8\ub2e4\ub9cc Swift\ub85c\ubd80\ud130 \uc0ac\uc6a9\ud560 \ub54c\uc5d0 \uadc0\ucc2e\uc740 \uc810\uc774 \ud55c \ubd80\ubd84 \ub0a8\uc544 \uc788\uc2b5\ub2c8\ub2e4. Generated Interface\ub97c \ubd10 \ubd05\uc2dc\ub2e4.<\/p>\n
public class MNPerson : NSObject {\r\n    public var name: String\r\n    public var age: UInt\r\n    public var items: [AnyObject]?\r\n    public func hey() -> String\r\n    public init(name: String, age: UInt)\r\n}\r\n<\/code><\/pre>\n
items<\/code> \ud504\ub85c\ud37c\ud2f0\uac00 AnyObject<\/code>\uc758 \ubc30\uc5f4\uc774 \ub418\uc5b4 \uc788\uc2b5\ub2c8\ub2e4. \ud558\ub098\ud558\ub098 \uce90\uc2a4\ud2b8 \ud558\ub294 \uac83\ub3c4 \uadc0\ucc2e\uc2b5\ub2c8\ub2e4. \uc5ec\uae30\uc11c\ub294 items<\/code>\uc5d0 \uc313\uc5ec\uc788\ub294 \uac83\uc740 \ubb38\uc790\uc5f4\uc774\ub77c \ud55c\uc815\ud574\uc11c Generics\uc758 \uc124\uc815\uc744 \ud558\uaca0\uc2b5\ub2c8\ub2e4.<\/p>\n
NS_ASSUME_NONNULL_BEGIN\r\n\r\n@interface MNPerson : NSObject\r\n@property (nonatomic, copy) NSString *name;\r\n@property (nonatomic) NSUInteger age;\r\n@property (nullable, nonatomic, copy) NSArray<NSString*> *items;\r\n- (NSString*)hey;\r\n- (instancetype)initWithName:(NSString*)name age:(NSUInteger)age;\r\n@end\r\nNS_ASSUME_NONNULL_END\r\n<\/code><\/pre>\n
items<\/code> \ud504\ub85c\ud37c\ud2f0\uc5d0 \ub300\ud558\uc5ec NSString<\/code>\uc744 \uc9c0\uc815\ud588\uc2b5\ub2c8\ub2e4. Generated Interface\ub97c \ubd10 \ubd05\uc2dc\ub2e4.<\/p>\n
public class MNPerson : NSObject {\r\n    public var name: String\r\n    public var age: UInt\r\n    public var items: [String]?\r\n    public func hey() -> String\r\n    public init(name: String, age: UInt)\r\n}\r\n<\/code><\/pre>\n
\uc704\uc640 \uac19\uc774 [String]<\/code>\uc73c\ub85c \ub418\uc5b4 \uc788\ub294 \uac83\uc744 \uc54c \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n
\uc774\ub807\ub4ef \uad6c\ud604\uc744 \ud655\uc778\ud558\uba74\uc11c Swift\ub85c\ubd80\ud130 \uc774\uc6a9\ud558\uae30 \uc27d\ub3c4\ub85d \ud574 \uac00\ub294 \uac83\uc774 \uac00\ub2a5\ud569\ub2c8\ub2e4.<\/p>\n
\uc815\ub9ac<\/h2>\n
\ucf54\ub4dc\uc591\uc801\uc73c\ub85c \ubd24\uc744 \ub54c \uadf8\ub807\uac8c\uae4c\uc9c0 \ub9ce\uc774 \uc7ac\uc791\uc131\ud558\uc9c0 \uc54a\ub354\ub77c\ub3c4 Swift\uc5d0\uc11c \uc0ac\uc6a9\ud558\uae30 \uc27d\uac8c \uc778\ud130\ud398\uc774\uc2a4\ub97c \uc218\uc815\ud558\ub294 \uac83\uc774 \uac00\ub2a5\ud569\ub2c8\ub2e4.<\/p>\n
\uc5b4\ub5bb\uac8c \uad6c\ud604\ub418\uc5c8\ub294\uc9c0 \ud30c\uc545\ub418\uc5b4 \uc788\ub294 \uacbd\uc6b0\uc5d0\ub294 \uc774\uc640 \uac19\uc740 Nullability\uc640 Generics\ub97c \uc9c0\uc815\ud558\ub294 \uac83\uc774 \uae30\uc874\uc758 Objective-C\uc758 \ucf54\ub4dc\ub97c Swift\ubd80\ud130 \uc0ac\uc6a9\ud558\uae30 \uc27d\uac8c \ud560 \uc218 \uc788\ub2e4\ub294 \uac83\uc5d0 \ud2c0\ub9b0 \ubd80\ubd84\uc740 \uc5c6\ub2e4\uace0 \uc0dd\uac01\ud569\ub2c8\ub2e4.<\/p>\n
\ub2e8\uc9c0, \uc774\uac83\ub4e4\uc744 \ubc14\uafb8\ub294 \uac83\uc740 \uc774\uc678\ub85c \uac04\ub2e8\ud558\uac8c \ub418\ub294 \uac83\uc740 \uc544\ub2cc \uac83 \uac19\uc740 \uc778\uc0c1\uc744 \uc90d\ub2c8\ub2e4. \uc774\uc720\ub77c\uace0 \ud55c\ub2e4\uba74 \ud55c \ubd80\ubd84\uc5d0\ub9cc nullable<\/code>\uacfc nonnull<\/code>\uc744 \uc9c0\uc815\ud558\ub294 \uac83\uc774 \ubd88\uac00\ub2a5\ud558\ub2e4\uac70\ub098 \ub098\ub984\ub300\ub85c \ud070 \ud074\ub798\uc2a4\uac00 \ub41c\ub2e4\uba74 nullable<\/code>\uc774\ub77c\uac70\ub098 nonnull<\/code>\uc778 \uac83\uc744 \uac04\ub2e8\ud558\uac8c \ud310\ub2e8\ud560 \uc218 \uc5c6\ub294 \uacbd\uc6b0\uac00 \ub9ce\uc544\uc9c4\ub2e4\ub294 \uc778\uc0c1\uc744 \uc8fc\uae30 \ub54c\ubb38\uc785\ub2c8\ub2e4.<\/p>\n
Objective-C\uc758 \uacbd\uc6b0 \uae30\ubcf8\uc801\uc73c\ub85c\ub294 nullable<\/code>\uc774 \ub41c\ub2e4\uace0 \uc0dd\uac01\ud558\uc9c0\ub9cc, Swift\uc5d0\uc11c \uc774\uc6a9\ud560 \ub54c\uc5d0\ub294 Optional\ub85c\uc368 \ucde8\uae09\ub418\uc9c0 \uc54a\uc73c\uba74 \uc548\ub418\uae30 \ub584\ubb38\uc5d0 \ub2e8\uc21c\ud558\uac8c nullable<\/code>\ub85c \ubc14\uafb8\ub294 \uac83\uc5d0\ub294 \ud070 \uac15\uc810\uc744 \ub290\ub084 \uc218 \uc5c6\uc2b5\ub2c8\ub2e4.<\/p>\n
\uadf8\ub798\ub3c4 Optional\ub85c\uc368 \ucde8\uae09\ub418\uc5b4\uc9c0\ub294 \uac83\uc774 \uac15\uc810\uc774\ub77c\uace0 \uc0dd\uac01\ud558\uba70 AnyObject<\/code>\uc758 \uce90\uc2a4\ud305\uc774 \uc904\uc5b4\ub4e0\ub2e4\ub294 \uac83\uc740 Swift\ucf54\ub4dc\ub97c \uc791\uc131\ud574\ub098\uac00\ub294\ub370 \ud070 \uac15\uc810\uc774 \ub420 \uac83\uc774\ub77c \uc0dd\uac01\ud569\ub2c8\ub2e4.<\/p>\n
\ucc38 \uace0<\/h2>\n