CS 3060: Programming Languages

The Scalable Language

Robert C. Green II, Ph.D.

XML

                        
val movies =
    
        Pirates of the Caribbean
        Edward Scissorhands
    
                        
                    

                        
movies.text
val movieNodes = movies \ "movie"
movieNodes(0)
movieNodes(0) \ "@genre"
                        
                    

Pattern Matching

                        
def fact(n: Int): Int =
    if (n == 0) { 1 }
    else        { n * fact(n - 1) }
                        
                    

                        
def fact(n: Int): Int = n match {
    case 0 => 1
    case n => n * fact(n - 1)
  }
                        
                    

Pattern Matching

                        
def fact(n: Int): Int = n match {
    case 0 => 1
    case n => n * fact(n - 1)
  }
                        
                    

                        
def factorial(n: Int): Int = n match {
    case 0 => 1
    case x if x > 0 => factorial(n - 1) * n
}
                        
                    

Pattern Matching

                        
def toYesOrNo(choice: Int): String = choice match {
    case 1 => "yes"
    case 0 => "no"
    case _ => "error"
  }
                        
                    

                        
def toYesOrNo(choice: Int): String = choice match {
    case 1 | 2 | 3 => "yes"
    case 0 => "no"
    case _ => "error"
  }
                        
                    

Pattern Matching

                        
def f(x: Any): String = x match {
    case i:Int => "integer: " + i
    case _:Double => "a double"
    case s:String => "I want to say " + s
  }
                        
                    

Regular Expressions

Concurrency

Assignment

Keep working on the Assignment. Incorporate functional things