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/Applications/scala-2.7.7.final/bin/scala ; exit;
howdy
D-69-91-165-161:~ stuartreges$ /Applications/scala-2.7.7.final/bin/scala ; exit;Welcome to Scala version 2.7.7.final (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_15).
Type in expressions to have them evaluated.
Type :help for more information.

scala> 2 + 2
res0: Int = 4

scala> 2 * 3 % 7
res1: Int = 6

scala> res1
res2: Int = 6

scala> 3.4
res3: Double = 3.4

scala> 2.toString
res4: java.lang.String = 2

scala> 3.4.toString
res5: java.lang.String = 3.4

scala> true.toString
res6: java.lang.String = true

scala> "hello"        
res7: java.lang.String = hello

scala> 'c'
res8: Char = c

scala> val x = 2.2 * 3
x: Double = 6.6000000000000005

scala> x = 14.5
<console>:5: error: reassignment to val
       x = 14.5
         ^

scala> val x = "hello"
x: java.lang.String = hello

scala> x
res10: java.lang.String = hello

scala> var x = 3.4
x: Double = 3.4

scala> x = 14.5
x: Double = 14.5

scala> (x : Double) => x * x
res12: (Double) => Double = <function>

scala> ((x : Double) => x * x)(4.2)
res13: Double = 17.64

scala> val f = (x : Double) => x * x
f: (Double) => Double = <function>

scala> f(3.4)
res14: Double = 11.559999999999999

scala> val compare = (s1 : String, s2 : String) => s1.length > s2.length
compare: (String, String) => Boolean = <function>

scala> compare("hello", "there")
res15: Boolean = false

scala> if (2 < 3) 14 else 72     
res16: Int = 14

scala> if (2 > 3) 14 else 72
res17: Int = 72

scala> if (2 > 3) 14 else "foo"
res18: Any = foo

scala> if (2 > 3) 14 else 17.5 
res19: AnyVal = 17.5

scala> if (2 > 3) 14 else true
res20: AnyVal = true

scala> def f(n : Int) = 2 * n
f: (Int)Int

scala> f(17)
res21: Int = 34

scala> def fact(n : Int) = if (n == 0) 1 else n * fact(n - 1)  
<console>:4: error: recursive method fact needs result type
       def fact(n : Int) = if (n == 0) 1 else n * fact(n - 1)
                                                  ^

scala> def fact(n : Int) : Int = if (n == 0) 1 else n * fact(n - 1)
fact: (Int)Int

scala> fact(10)
res22: Int = 3628800

scala> fact(15)
res23: Int = 2004310016

scala> fact(240)
res24: Int = 0

scala> def fact(n : BigInt) : BigInt = if (n == 0) 1 else n * fact(n - 1)
fact: (BigInt)BigInt

scala> fact(240)
res25: BigInt = 40678853636470581204935759214868853101720512591828271460697559690814869189255851040091007297283485229238208902458700986591471560519057325631473815990984592447524630276881157053717046282863266212384565433072676086125451683377796691387594517603959682174236179543307370341645964969639868177222522210597680808524899409956055791719996669160040429652938967998005980799852641951...
scala> x = 84903849023482390
<console>:1: error: integer number too large
       x = 84903849023482390
           ^

scala> Nil
res26: Nil.type = List()

scala> 3 :: Nil
res27: List[Int] = List(3)

scala> 1 :: 2 :: 3 :: Nil
res28: List[Int] = List(1, 2, 3)

scala> val lst = List(1, 3, 18, 47, 902, 2, -8)
lst: List[Int] = List(1, 3, 18, 47, 902, 2, -8)

scala> val lst2 = List(3, 84.5, 17, 19.2)
lst2: List[AnyVal] = List(3, 84.5, 17, 19.2)

scala> val lst2 = List(3, 84.5, 17, 19.2, "hello")
lst2: List[Any] = List(3, 84.5, 17, 19.2, hello)

scala> hd(lst)
<console>:6: error: not found: value hd
       hd(lst)
       ^

scala> lst.head
res30: Int = 1

scala> lst.tail
res31: List[Int] = List(3, 18, 47, 902, 2, -8)

scala> lst.length
res32: Int = 7

scala> lst
res33: List[Int] = List(1, 3, 18, 47, 902, 2, -8)

scala> lst2
res34: List[Any] = List(3, 84.5, 17, 19.2, hello)

scala> lst ::: lst2
res35: List[Any] = List(1, 3, 18, 47, 902, 2, -8, 3, 84.5, 17, 19.2, hello)

scala> def stutter(lst : List[Any]) =
     |     if (lst.isEmpty) Nil else lst.head :: lst.head :: stutter(lst.tail)
<console>:6: error: recursive method stutter needs result type
           if (lst.isEmpty) Nil else lst.head :: lst.head :: stutter(lst.tail)
                                                             ^

scala> def stutter(lst : List[Any]) : List[Any] =                             
     |     if (lst.isEmpty) Nil else lst.head :: lst.head :: stutter(lst.tail)
stutter: (List[Any])List[Any]

scala> lst
res36: List[Int] = List(1, 3, 18, 47, 902, 2, -8)

scala> stutter(lst)
res37: List[Any] = List(1, 1, 3, 3, 18, 18, 47, 47, 902, 902, 2, 2, -8, -8)

scala> 2 +
<console>:5: error: ambiguous reference to overloaded definition,
both method + in class Int of type (Double)Double
and  method + in class Int of type (Float)Float
match expected type ?
       2 +
         ^

scala> if (true) 3 else
     | 4
res39: Int = 3

scala> if (true) 3     

scala> val x = if (true) 3
x: Unit = ()

scala> x

scala> val x = if (false) 3
x: Unit = ()

scala> x

scala> val x = if (false) then 3
<console>:1: error: ';' expected but integer literal found.
       val x = if (false) then 3
                               ^

scala> val x = if (false) then 3;
<console>:1: error: ';' expected but integer literal found.
       val x = if (false) then 3;
                               ^

scala> val x = if (false) 3;     
x: Unit = ()

scala> x

scala> lst
res44: List[Int] = List(1, 3, 18, 47, 902, 2, -8)

scala> lst.map((x : Int) => x * x)
res45: List[Int] = List(1, 9, 324, 2209, 813604, 4, 64)

scala> lst.filter((x : Int) => x % 2 == 0)
res46: List[Int] = List(18, 902, 2, -8)

scala> lst.reduceLeft((x : Int, y : Int) => x + y)     
res47: Int = 965

scala> lst.sort((x : Int, y : Int) => x < y)      
res48: List[Int] = List(-8, 1, 2, 3, 18, 47, 902)

scala> lst.sort((x : Int, y : Int) => x > y)
res49: List[Int] = List(902, 47, 18, 3, 2, 1, -8)

scala> (0 /: lst) {(x, y) => x + y}
res50: Int = 965

scala> lst.partition((x : Int) => x < 10)
res51: (List[Int], List[Int]) = (List(1, 3, 2, -8),List(18, 47, 902))

scala> def quicksort(lst : List[Int]) : List[Int] =
     |     if (lst.length <= 1) lst else {
     |         val (a, b) = lst.partition((x : Int) => x <= lst.head)
     |         quicksort(a) ::: (lst.head :: quicksort(b))
     | }
quicksort: (List[Int])List[Int]

scala> def quicksort(lst : List[Int]) : List[Int] =                  
     |     if (lst.length <= 1) lst else {                           
     |         val (a, b) = lst.tail.partition((x : Int) => x <= lst.head)
     |         quicksort(a) ::: (lst.head :: quicksort(b))                
     | }                                                                  
quicksort: (List[Int])List[Int]

scala> quicksort(lst)
res52: List[Int] = List(-8, 1, 2, 3, 18, 47, 902)

scala> lst(3)
res53: Int = 47

scala> lst
res54: List[Int] = List(1, 3, 18, 47, 902, 2, -8)

scala> lst.slice(2, 5)
res55: List[Int] = List(18, 47, 902)

scala> 1 to 10
res56: Range.Inclusive = Range(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

scala> for (n <- 1 to 10) println n
<console>:5: error: value n is not a member of Unit
       for (n <- 1 to 10) println n
                                  ^

scala> for (n <- 1 to 10) println(n)
1
2
3
4
5
6
7
8
9
10

scala> for (n <- 1 to 10) println(n)      
1
2
3
4
5
6
7
8
9
10

scala> ("blastoff" /: (1 to 10)) ((x, y) => y + ", " + x)
res60: java.lang.String = 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, blastoff

scala> (2, 3)
res61: (Int, Int) = (2,3)

scala> (2, 3.4)
res62: (Int, Double) = (2,3.4)

scala> (2, 3.4, "hello")
res63: (Int, Double, java.lang.String) = (2,3.4,hello)

scala> val (x, y, z) = (2, 3.4, "hello")
x: Int = 2
y: Double = 3.4
z: java.lang.String = hello

scala> class Data(val n: Int, var x : Double)
defined class Data

scala> val a = new Data
<console>:5: error: wrong number of arguments for constructor Data: (Int,Double)Data
       val a = new Data
               ^

scala> val a = new Data(13, 14.5)
a: Data = Data@1515c044

scala> a.x
res64: Double = 14.5

scala> a.n
res65: Int = 13

scala> a.x_$eq(17.4)

scala> a.x
res67: Double = 17.4

scala> a.getClass.getMethods
res68: Array[java.lang.reflect.Method] = Array(public double Data.x(), public int Data.$tag() throws java.rmi.RemoteException, public int Data.n(), public void Data.x_$eq(double), public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException, public final void java.lang.Object.wait() throws java.lang.InterruptedException, public final native void java.lang.Ob...

scala> for (m <- a.getClass.getMethods) println(m)
public double line85$object$$iw$$iw$Data.x()
public int line85$object$$iw$$iw$Data.$tag() throws java.rmi.RemoteException
public int line85$object$$iw$$iw$Data.n()
public void line85$object$$iw$$iw$Data.x_$eq(double)
public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException
public final void java.lang.Object.wait() throws java.lang.InterruptedException
public final native void java.lang.Object.wait(long) throws java.lang.InterruptedException
public native int java.lang.Object.hashCode()
public final native java.lang.Class java.lang.Object.getClass()
public boolean java.lang.Object.equals(java.lang.Object)
public java.lang.String java.lang.Object.toString()
public final native void java.lang.Object.notify()
public final native void java.lang.Object.notifyAll()

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