YYClassIvarInfo.h.m

/**
 Instance variable information.
 */
@interface YYClassIvarInfo : NSObject
@property (nonatomic, assign, readonly) Ivar ivar;              ///< ivar opaque struct
@property (nonatomic, strong, readonly) NSString *name;         ///< Ivar's name
@property (nonatomic, assign, readonly) ptrdiff_t offset;       ///< Ivar's offset
@property (nonatomic, strong, readonly) NSString *typeEncoding; ///< Ivar's type encoding
@property (nonatomic, assign, readonly) YYEncodingType type;    ///< Ivar's type

/**
 Creates and returns an ivar info object.
 
 @param ivar ivar opaque struct
 @return A new object, or nil if an error occurs.
 */
- (instancetype)initWithIvar:(Ivar)ivar;
@end

@implementation YYClassIvarInfo

- (instancetype)initWithIvar:(Ivar)ivar {
    if (!ivar) return nil;
    self = [super init];
    _ivar = ivar;
    const char *name = ivar_getName(ivar);
    if (name) {
        _name = [NSString stringWithUTF8String:name];
    }
    _offset = ivar_getOffset(ivar);
    const char *typeEncoding = ivar_getTypeEncoding(ivar);
    if (typeEncoding) {
        _typeEncoding = [NSString stringWithUTF8String:typeEncoding];
        _type = YYEncodingGetType(typeEncoding);
    }
    return self;
}

@end