Scala Match Expression

Scale Match Expression

Solution

  • Normal
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    val month = i match {
    	case 1  => "January"
    	case 2  => "February"
    	case 3  => "March"
    	case 4  => "April"
    	case 5  => "May"
    	case 6  => "June"
    	case 7  => "July"
    	case 8  => "August"
    	case 9  => "September"
    	case 10 => "October"
    	case 11 => "November"
    	case 12 => "December"
    	case _  => "Invalid month"  // the default, catch-all
    }

Discussion

  • As demonstrated in other recipes, you aren’t limited to matching only integers; the match expression is incredibly flexible:
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    def getClassAsString(x: Any):String = x match {
    	case s: String => s + " is a String"
    	case i: Int => "Int"
    	case f: Float => "Float"
    	case l: List[_] => "List"
    	case p: Person => "Person"
    	case _ => "Unknown"
    }

Compare

  • Use Compare Method
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    def checkData(i:Int) ={
    	i compare 10 match {
    		case 1 => println("i > 10")
    		case 0 => println("i = 10")
    		case -1 => println("i < 10")
    	}
    }