Scala的含義：「C @請求」

我有一個關於下面的代碼部分的問題：Scala的含義：「C @請求」

sealed trait Claim { val claimId: Int } 
case class Full(val claimId: Int) extends Claim 
case class Partial(val claimId: Int, percentage: Double) extends Claim 
case class Generic(override val claimId: Int) extends Claim 

case class Location(stateCode: Option[String], zipCode: Option[String]) 
case class Req(productId: String, location: Location, claim: Claim) 

object PricingSystem { 
    type PC = Tuple2[Req, Option[Double]] 

    def handleFullClaim: PartialFunction[PC, PC] = { 
    case ([email protected](id, l, Full(claimId)), basePrice) => (c, basePrice.map(_ + 10)) 
    } 

    def handlePartialClaim: PartialFunction[PC, PC] = { 
    case ([email protected](id, l, Partial(claimId, percentage)), basePrice) => (c, basePrice.map(_ + 20)) 
    } 

    def handleZipCode: PartialFunction[PC, PC] = { 
    case ([email protected](id, Location(_, Some(zipCode)), _), price) => (c, price.map(_ + 5)) 
    } 

    def handleStateCode: PartialFunction[PC, PC] = { 
    case ([email protected](id, Location(Some(stateCode), _), _), price) => (c, price.map(_ + 10)) 
    } 

    def claimHandlers = handleFullClaim orElse handlePartialClaim 
    def locationHandlers = handleZipCode orElse handleStateCode 

    def default: PartialFunction[PC, PC] = { case p => p } 
    def priceCalculator: PartialFunction[PC, PC] = 
    (claimHandlers andThen locationHandlers) orElse default 

    def main(args: Array[String]) = { 
    priceCalculator((Req("some product", Location(None, Some("43230")), Full(1)), Some(10))) match { 
     case (c, finalPrice) => println(finalPrice) 
    } 
    priceCalculator((Req("some product", Location(None, None), Generic(10)), Some(10))) match { 
     case (c, finalPrice) => println(finalPrice) 
    } 
    } 

}

是什麼下面的代碼片段意味着階：[email protected]？特別是：@在這裏簽字是什麼意思？

來源

2014-01-21 balteo

看到這個確切的問題：http://stackoverflow.com/questions/20748858/pattern-matching-symbol/20748908#20748908 – wheaties

模式匹配@將左側的變量綁定到右側匹配的值。然後在您的代碼c中可以參考匹配的模式的值。

看到這個http://www.artima.com/pins1ed/case-classes-and-pattern-matching.html

來源

2014-01-21 17:30:11 Brian

感謝「的@模式匹配的含義」。如果我理解正確，''c'「是」case class Req（productId：String，location：Location，claim：Claim）'「的實例？我對嗎？ – balteo

不一定; 'c'匹配'Req（id，l，Full（claimId））'模式。「@」符號允許您指定捕獲值和必須與捕獲值匹配的模式。 –

Scala的含義：「C @請求」

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