RAC(self.loginButton,enabled)  = [self.textFiled.rac_textSignal  map:^id(NSString *value) {
    return @(value.length>3);
}];

 - (RACSignal *)rac_textSignal {
	@weakify(self);
	return [[[[[RACSignal
		defer:^{
			@strongify(self);
			return [RACSignal return:self];
		}]
		concat:[self rac_signalForControlEvents:UIControlEventAllEditingEvents]]
		map:^(UITextField *x) {
			return x.text;
		}]
		takeUntil:self.rac_willDeallocSignal]
		setNameWithFormat:@"%@ -rac_textSignal", self.rac_description];
}

#define RACObserve(TARGET, KEYPATH) \
	({ \
		_Pragma("clang diagnostic push") \
		_Pragma("clang diagnostic ignored \"-Wreceiver-is-weak\"") \
		__weak id target_ = (TARGET); \
		[target_ rac_valuesForKeyPath:@keypath(TARGET, KEYPATH) observer:self]; \
		_Pragma("clang diagnostic pop") \
	})

- (RACSignal *)rac_valuesForKeyPath:(NSString *)keyPath observer:(__weak NSObject *)observer {
	return [[[self
		rac_valuesAndChangesForKeyPath:keyPath options:NSKeyValueObservingOptionInitial observer:observer]
		map:^(RACTuple *value) {
			// -map: because it doesn't require the block trampoline that -reduceEach: uses
			return value[0];
		}]
		setNameWithFormat:@"RACObserve(%@, %@)", self.rac_description, keyPath];
}

rac_valuesAndChangesForKeyPath:keyPath options:NSKeyValueObservingOptionInitial observer:observer]

RAC(self.loginButton,enabled) =[ [RACObserve(self.textFiled, text)  merge:self.textFiled.rac_textSignal ] map:^id(NSString *value) {
     return @(value.length>3);
}];

var array:Array = [1,2]

array.appendContentsOf([2,3,4])
array.insert(1, atIndex: 0)

var url = NSURL(string: "randomLoacation")!

if url.fileURL {}
var x = url.URLByAppendingPathComponent("file.txt")

//Swift.Array
var array:Array = [1,2]

array.append(contentsOf: [2,3,4])
array.insert(1, at: 0) //index没有什么特定信息,只是重复

//Foudation.NSURL
var url = NSURL(string: "randomLoacation")!
if url.isFileURL {} //意思更明确
var x = url.appendingPathComponent("file.txt")

func myFunction(a: Int , b: Int , c: Int){

}

myFunction(42, b: 57, c: 39)

func myFunction(a: Int , b: Int , c: Int){
    
}

myFunction(a: 10, b: 10, c: 10)

func myFunction(_ a: Int , b: Int , c: Int){
    
}

myFunction(10, b: 10, c: 10)

func anyCommon<T: SequenceType, U: SequenceType
    where T.Generator.Element : Equatable,
    T.Generator.Element == U.Generator.Element>(lhs: T, rhs: U) -> Bool{
    print("here")
    return true;

}

func anyCommons<T: Sequence, U: Sequence>(lhs: T, rhs: U) -> Bool
    where T.Element: Equatable,T.Element == U.Element
{
    print("here")
    return true;
    
}

func plusOne(_ a : Int) ->Int{
         print(a)
         return a+1
     }
     
     plusOne(3) //得到警告 Result of call to 'plusOne' is unused

func plusOne(_ a : Int) ->Int{
    print(a)
    return a+1
}

_ =  plusOne(3)

@discardableResult
func plusOne(_ a : Int) ->Int{
    print(a)
    return a+1
}

plusOne(3)

let collection = ["a","b","c","d"]

var i = collection.startIndex

swift 2 : var next = i.successor()

var next = collection.index(after: 2)

let v = 2 * Float(M_PI)

let v = 2 * Float.pi

let anotherV = 2.0 * .pi / 180

func f(value: Int!){
    let x = value + 1 // x 是 Int 类型 - 强制解包
    let y = value     // y 是 Int!

}

func f(value: Int!){
    let x = value + 1 // x 是 Int 类型 - 强制解包
    let y = value     // y 是 Int?

}

let param = (20,"kenny","male")

func personInfo(age: Int ,_ name: String ,_ gender: String){

}

personInfo(param)

//也可以不省略标签

let param = (age:20, name:"kenny", gender:"male")

func personInfo(age age: Int , name: String , gender: String){

}

personInfo(param)

func GUILog<T>(_ message: T, fileName: String = #function, methodName: String = #function, lineNumber: Int = #line) {
    #if DEBUG
    print("\(methodName)[\(lineNumber)]:\(message)")
    #endif
}

func GUILog<T>(_ message: T, fileName: String = #function, methodName: String = #function, lineNumber: Int = #line) {
    #if DEFAULT
    print("\(methodName)[\(lineNumber)]:\(message)")
    #endif
}

class Person{
    
    var labelText:String
        {
        set(newValue){
            self.labelText = newValue
        }
   
    }
    
}

“In addition to stored properties, classes, structures, and enumerations can define computed properties, which do not actually store a value. Instead, they provide a getter and an optional setter to retrieve and set other properties and values indirectly.”

class Person{
    
    var labelText:String = "great"
        {
        willSet{
            print("labeltext will change!")
            
        }
        didSet{
            print("labeltext did change!")
//            labelText = "defalut"
        }
    }
}

labeltext will change!
labeltext did change!
11

pod lib create GUICodeSnippet

pod install

git tag -a 0.1.0 -m "初始版本"

通常的git push不会将标签对象提交到git服务器，我们需要进行显式的操作：
git push origin 0.1.2 # 将v0.1.2标签提交到git服务器
或者
git push origin –tags # 将本地所有标签一次性提交到git服务器
验证标签成功
git tag #查看标签

稍后, 邮箱会收到邮件, 点击链接即可

``` pod trunk push BlinkingLabel.podspec

pod search GUICodeSnippet

kenny@kenny:~|⇒  /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
-e:77: warning: Insecure world writable dir /usr/local/bin in PATH, mode 040777
It appears Homebrew is already installed. If your intent is to reinstall you
should do the following before running this installer again:
    ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/uninstall)"
The current contents of /usr/local are bin Cellar CODEOFCONDUCT.md CONTRIBUTING.md etc include lib Library LICENSE.txt opt README.md sbin share SUPPORTERS.md var .git .gitignore