// 0、NSObject+RACPropertySubscribing.h

#define RACObserve(TARGET, KEYPATH) _RACObserve(TARGET, KEYPATH)

#define _RACObserve(TARGET, KEYPATH) \
({ \
    __weak id target_ = (TARGET); \
    [target_ rac_valuesForKeyPath:@keypath(TARGET, KEYPATH) observer:self]; \
})

 

    // 1、NSObject+RACPropertySubscribing.h      信号的方式///map映射了--值

    [self rac_valuesForKeyPath:[<#(nonnull NSString *)#>] observer:<#(NSObject * _Nonnull __weak)#>]





    // 2、 NSObject+RACPropertySubscribing.h     信号的方式///值、字典

    [self  rac_valuesAndChangesForKeyPath:<#(nonnull NSString *)#> options:<#(NSKeyValueObservingOptions)#> observer:<#(NSObject * _Nonnull __weak)#>]






    // 3、NSObject+RACKVOWrapper.h   block的方式//处理递归调用-----keypath由多级路径组成

    [self rac_observeKeyPath:<#(NSString *)#> options:<#(NSKeyValueObservingOptions)#> observer:<#(NSObject *__weak)#> block:<#^(id value, NSDictionary *change, BOOL causedByDealloc, BOOL affectedOnlyLastComponent)block#>]

    




    // 4、RACKVOTrampoline.h  block的方式
    - (instancetype)initWithTarget:(__weak NSObject *)target observer:(__weak NSObject *)observer keyPath:(NSString *)keyPath options:(NSKeyValueObservingOptions)options block:(RACKVOBlock)block 

RACObserve 与系统的不冲突;
rac_signalForSelector有冲突RACObserve；

rac_signalForSelector先调用、RACObserve后调用；
如果是相反，则发生crash；rac_alias_setKvoValue:]: unrecognized selector sent to instance 0x7ff1e3e12570'

rac_signalForSelector
RACObserve
addObserver: forKeyPath: options

    // 22 TextViewBindViewController_RACSelectorSignal ///NSKVONotifying_TextViewBindViewController
    //    [[self rac_signalForSelector:@selector(intValue1:float2:char:)] subscribeNext:^(RACTuple * _Nullable x) {
    //        NSLog(@"111->  %@" ,  x);
    //    } error:^(NSError * _Nullable error) {
    //        NSLog(@"222->: %@" ,error );
    //    } completed:^{
    //        NSLog(@"completed!!");
    //    }];
    [[self  rac_signalForSelector:@selector(setKvoValue:)] subscribeNext:^(RACTuple * _Nullable x) {
        NSLog(@"%s %@ --%d",__func__, x, __LINE__);
    }];
    NSString*s4=[NSString stringWithUTF8String: object_getClassName(self) ];
    
 
    // 11 NSKVONotifying_TextViewBindViewController_RACSelectorSignal  // NSKVONotifying_TextViewBindViewController
    [RACObserve(self, kvoValue)  subscribeNext:^(id  _Nullable x) {
        NSLog(@"%s %@ --%d",__func__, x, __LINE__);
    }error:^(NSError * _Nullable error) {
        NSLog(@"%s  --%d",__func__, __LINE__);
    }completed:^{
        NSLog(@"%s  --%d",__func__, __LINE__);
    }];
    NSString*s3=[NSString stringWithUTF8String: object_getClassName(self) ];
    

    
    // 33   NSKVONotifying_TextViewBindViewController_RACSelectorSignal///NSKVONotifying_TextViewBindViewController
    [self addObserver:self forKeyPath:@"kvoValue" options:NSKeyValueObservingOptionInitial|NSKeyValueObservingOptionNew context:nil];
    NSString*s5=[NSString stringWithUTF8String: object_getClassName(self) ];
    

    NSLog(@"%s %@,%@,%@ --%d",__func__, s3,s4,s5, __LINE__);
    [self intValue1:1 float2:1.2 char:@"1".UTF8String];
    [self setKvoValue:@"111"];
    [self setValue:@"222" forKey:@"kvoValue"];
    _kvoValue=@"333";