A brief talk on the swift function of curry (currying)

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The following is a simple way to say that the function of the swift language is simply to divide the function that receives multiple parameters into several "nested" single-parameter functions.

So that no one can understand, we combine an example for everyone to simply say.

We need to define a function A, which returns a function B, and the function B creates a big spider. Why return to the big spider indirectly, because this cat is afraid of the big spider, so dare not directly return to the big spider;)

The first is the spider's Class:

class Spider:CustomStringConvertible {    let name:String    let leg:Int    var description:String{        return"蜘蛛(\(name) leg:\(leg))"    }    init(name:String,leg:Int){        self.= name        self.= leg    }}

Because we don't want to create a big spider directly, we need a function that returns a function:

func createSpawnSpiderFunc(name:String)->()->Spider{    func spwanSpider()->Spider{        return Spider(nameleg8)    }    return spwanSpider}let x = createSpawnSpiderFunc("BigSpider")let//leg:8)

Looks good, but the above method to limit the spider's legs to 8, which is not very good, so we make some adjustments:

func createSpawnSpiderFunc2(name:String)->(Int)->Spider{    func spwanSpider(leg:Int)->Spider{        return Spider(nameleg: leg)    }    return spwanSpider}let y = createSpawnSpiderFunc2("XLegSpider")let spiderXLeg = y(16//leg:16)

We can simplify the function appropriately:

func createSpawnSpiderFunc3(name:String)->(Int)->Spider{    returnin        return Spider(nameleg: leg)    }}

You would say that this function is not pretty, because behind the two-and-a-tail, indeed! Not only is it not elegant and it's easy to get the novice around, so we turn the function: Curry smecta:

func createSpawnSpiderFuncCurry(name:String)(leg:Int)->Spider{    return Spider(nameleg: leg)}

We call this:

let 蜘蛛 = createSpawnSpiderFuncCurry("大蜘蛛"121//蜘蛛(大蜘蛛 leg:121)

Note that the above function looks like the return type is spider, but it is not! It still returns a function! Prove to you:

let 创建超级大蜘蛛 = createSpawnSpiderFuncCurry("超级大蜘蛛")let100000//蜘蛛(超级大蜘蛛 leg:100000)

A brief talk on the swift function of curry (currying)