(* CS:3820, Fall 2016 *)
(* Cesare Tinelli *)
(* The University of Iowa *)

(* F# examples seen in class *)


(* Immutable record types *)

type employeeType = { 
       id : int ;     
       name : string ; 
       age : int ; 
       salary : float ; 
       dept : char
     }


let e = { id = 1098; name = "Joe Bull"; age = 22; salary = 3400.4; dept = 'S' }

e.name

e.dept

let { id = i; name = n } = e


let e1 = { e with age = 40; dept = 'A' }

e


// semicolon separator can be replaced by a new line character
let e = { id = 1098
          name = "Joe Bull"
          age = 22
          salary = 3400.4
          dept = 'S' 
         }


(* Mutable record types *)

type mut_rec = {
       mutable x : int ;
       y : int
     }

let r = { x = 5; y = 3 }

// assignment 
r.x <- 10

r

r.y <- 110



type linkedList = { value : int ; mutable next : linkedList }


// mutable variables

let mutable z = 4

z <- 11

// while loops


while (z > 0) do (printfn "%i\n" z; z <- z - 1)


// semicolon separator can be replaced by a new line character
// and indentation
while (z > 0) do
  printfn "%i\n" z
  z <- z - 1