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ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Scala Programming Language
Georg Sauthoffgsauthof@techfak.uni-bielefeld.de
Universität BielefeldAG Praktische Informatik
June 1, 2010
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Scala
Multi-paradigm general purpose programming language byMartin Oderskysince 2003
functionalobject orientedimperative
eager evaluation (lazy annotations available)type inference (in a limited fashion)rich operator overloadingfor the JVMintegrates well with Java modules
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Example
1 o b j e c t Fac1 {2 de f f a c ( i : B i g I n t ) : B i g I n t = i match {3 case _ i f i == 1 => i4 case _ => i ∗ f a c ( i − 1)5 }6 de f main ( a r g s : Ar ray [ S t r i n g ] ) =7 p r i n t l n ( f a c ( I n t e g e r p a r s e I n t ( a r g s ( 0 ) ) ) )8 }
9 > module Main10 > where11 > import System ( getArgs )12
13 > f a c : : I n tege r −> I n tege r14 > f a c 1 = 115 > f a c i = i ∗ f a c ( i −1)16
17 > main = do18 > ( x :_) <− getArgs19 > putStrLn $ show $ f a c ( ( read x ) : : I n tege r )
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Example
1 o b j e c t Fac1 {2 de f f a c ( i : B i g I n t ) : B i g I n t = i match {3 case _ i f i == 1 => i4 case _ => i ∗ f a c ( i − 1)5 }6 de f main ( a r g s : Ar ray [ S t r i n g ] ) =7 p r i n t l n ( f a c ( I n t e g e r p a r s e I n t ( a r g s ( 0 ) ) ) )8 }9 > module Main10 > where11 > import System ( getArgs )12
13 > f a c : : I n tege r −> I n tege r14 > f a c 1 = 115 > f a c i = i ∗ f a c ( i −1)16
17 > main = do18 > ( x :_) <− getArgs19 > putStrLn $ show $ f a c ( ( read x ) : : I n tege r )
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Syntax
No offside rule;{}. in some contexts optionaltype declarations optional if type inference is possible(limited)
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Lambda functions
1 o b j e c t Reduce {2 de f mult ( l : Ar ray [ I n t ] ) : I n t =3 l r e d u c e L e f t { _ ∗ _ }4 // l . r e d u c e L e f t ( ( i , j ) => i ∗ j )5
6 de f main ( a r g s : Ar ray [ S t r i n g ] ) =7 p r i n t l n ( mult ( a r g s map { I n t e g e r p a r s e I n t _ } ) )8 }
9 > module Main10 > where11
12 > import System ( getArgs )13
14 > mult = f o l d l (∗ ) 115
16 > main = do17 > l <− getArgs18 > putStrLn $ show $ mult $ map (\ x −> ( read x ) : : I n tege r ) l
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Lambda functions
1 o b j e c t Reduce {2 de f mult ( l : Ar ray [ I n t ] ) : I n t =3 l r e d u c e L e f t { _ ∗ _ }4 // l . r e d u c e L e f t ( ( i , j ) => i ∗ j )5
6 de f main ( a r g s : Ar ray [ S t r i n g ] ) =7 p r i n t l n ( mult ( a r g s map { I n t e g e r p a r s e I n t _ } ) )8 }9 > module Main10 > where11
12 > import System ( getArgs )13
14 > mult = f o l d l (∗ ) 115
16 > main = do17 > l <− getArgs18 > putStrLn $ show $ mult $ map (\ x −> ( read x ) : : I n tege r ) l
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Lambda functions
reduce, foldr, map etc. are all member functions ofcollections like array, list ...in comparison to Haskell or C++ STL not very orthogonalhowever, they are implemented only once in the traitIterable
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Example
1 > module Main2 > where3 > import System4
5 > sep = f o l d r (\ b a −> i f b == ’ , ’ then [ ] : a6 e l s e ( b : ( head a ) ) : t a i l a ) [ [ ] ]7
8 > main = do9 > ( a : [ ] ) <− getArgs10 > putStrLn $ show $ sep a
11 i n t main ( i n t argc , char ∗∗ a rgv )12 {13 vec to r <s t r i n g > v ( 1 ) ;14 f o r e a c h ( char c , a rgv [ 1 ] )15 i f ( c == ’ , ’ ) v . r e s i z e ( v . s i z e ( )+1) ;16 e l s e v . back ( ) . push_back ( c ) ;17 f o r e a c h ( s t r i n g &s , v ) cout << s << ’ ’ ;18 cout << ’ \n ’ ; re tu rn 0 ;19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Example
1 > module Main2 > where3 > import System4
5 > sep = f o l d r (\ b a −> i f b == ’ , ’ then [ ] : a6 e l s e ( b : ( head a ) ) : t a i l a ) [ [ ] ]7
8 > main = do9 > ( a : [ ] ) <− getArgs10 > putStrLn $ show $ sep a11 i n t main ( i n t argc , char ∗∗ a rgv )12 {13 vec to r <s t r i n g > v ( 1 ) ;14 f o r e a c h ( char c , a rgv [ 1 ] )15 i f ( c == ’ , ’ ) v . r e s i z e ( v . s i z e ( )+1) ;16 e l s e v . back ( ) . push_back ( c ) ;17 f o r e a c h ( s t r i n g &s , v ) cout << s << ’ ’ ;18 cout << ’ \n ’ ; re tu rn 0 ;19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Example
1 o b j e c t Sep {2
3 // S i g n a t u r e ( Cur ry s yn tax ) :4 // f o l d R i g h t : (B) ( ( In t , B) => B)B5
6 de f sep ( s : S t r i n g ) : L i s t [ S t r i n g ] =7 s . f o l d R i g h t ( L i s t ( new S t r i n g ( " " ) ) )8 { (b , a ) => i f ( b == ’ , ’ ) ( new S t r i n g ) : : a9 e l s e ( b + ( a head ) ) : : ( a t a i l ) }10
11 de f main ( a r g s : Ar ray [ S t r i n g ] ) =12 p r i n t l n ( sep ( a r g s ( 0 ) ) )13
14 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Compile times
Thinkpad X200, excluding pre-heating runs, in seconds
ghc 6.10.4 -O2 scalac 2.7.5
Fac1 0.6 2Sep 0.4 2.1
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
OOP
no multiple inheritancebut, traitsGenerics
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Traits
don’t confuse with C++ traitslike interfaces, but may contain function bodiesno constructorsto implement unrelated/orthogonal aspectscan extend classes, traitsmay contain stateone class may ’implement’/’extend’ several traits . . .
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Trait Example
1 t r a i t ChangeL i s t ene r { de f change }2 c l a s s Widget { }3 c l a s s Button extends Widget with ChangeL i s t ene r {4 de f change = p r i n t l n ( " changed ! " )5 }6 t r a i t ChangeSender {7 p r i v a t e va r l = L i s t [ ChangeL i s t ene r ] ( )8 de f addChangeL i s t ene r ( a : ChangeL i s t ene r ) : Un i t =9 l : := a10 de f emitChanges ( ) = l f o r e a c h ( f => f . change )11 }12 c l a s s Base { }13 c l a s s Pane l extends Base with ChangeSender { }14 o b j e c t T r a i t {15 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {16 va r p = new Pane l ; va r b = new Button17 p . addChangeL i s t ene r ( b )18 p . emitChanges19 }20 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
C++ Trait
1 #i nc l ude <ios t r eam >2
3 t emp la t e <typename T>4 s t r u c t Number {5 enum { X = 0 } ;6 } ;7
8 t emp la t e <> s t r u c t Number<i n t > { enum { X = 23 } ; } ;9
10 t emp la t e <typename T> s t r u c t Number<T∗> { enum { X = 42 } ; } ;11
12 t emp la t e <typename T>13 vo id p r i n t ( const T &t ) { s td : : cout << Number<T>: :X << ’ \n ’ ; }14
15 i n t main ( ) {16 i n t ∗ i ; p r i n t ( i ) ;17 double a ; p r i n t ( a ) ;18 re tu rn 0 ;19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Verbatim XML support as language feature
1 o b j e c t Xml {2
3 v a l x = " bar "4
5 v a l doc = <xml><i s ><b loa ted >6 <e n t r y date="1">foo </ent ry >7 <e n t r y date="2">{ x }</ent ry >8 </b loa ted ></i s ></xml>9
10 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {11 p r i n t l n ( doc )12 v a l e s = doc \\ " e n t r y "13 p r i n t l n ( e s )14 v a l ds = doc \\ " e n t r y " f i n d { ( x ) =>15 ( x . a t t r i b u t e ( " date " ) != None16 && x . a t t r i b u t e ( " date " ) . ge t == "1" ) }17 p r i n t l n ( ds )18 }19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Case classes
1 a b s t r a c t c l a s s Tree2
3 case c l a s s Lea f ( s : S t r i n g ) extends Tree4 case c l a s s Br ( l : Tree , r : Tree ) extends Tree5
6 o b j e c t Case {7
8 de f depth ( a : Tree ) : I n t =9 a match {10 case Lea f ( s ) => 111 case Br ( l , r ) =>12 1 + ( Math max( depth ( l ) , depth ( r ) ) )13 }14
15 de f main ( a r g s : Ar ray [ S t r i n g ] ) =16 p r i n t l n ( depth (17 Br ( Br ( Lea f ( " a " ) , Br ( Lea f ( "b" ) ,18 Lea f ( " c " ) ) ) , Lea f ( "d" ) ) ) )19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Generics
1 a b s t r a c t c l a s s Tree [T]2 case c l a s s Lea f [T ] ( s : T) extends Tree [T]3 case c l a s s Br [T ] ( l : Tree [T] , r : Tree [T ] ) extends Tree [T]4
5 c l a s s He lpe r [T] {6 de f depth ( a : Tree [T ] ) : I n t =7 a match {8 case Lea f ( s ) => 19 case Br ( l , r ) =>10 1 + ( Math max( depth ( l ) , depth ( r ) ) )11 }12 }13 o b j e c t Gen {14 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {15 v a l h = new He lpe r [ S t r i n g ]16 p r i n t l n ( h . depth (17 Br ( Br ( Lea f ( " a " ) , Br ( Lea f ( "b" ) ,18 Lea f ( " c " ) ) ) , Lea f ( "d" ) ) ) )19 }20 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Inheritance vs. Pattern Matching
1 a b s t r a c t c l a s s Tree { de f depth : I n t }2
3 case c l a s s Lea f ( s : S t r i n g ) extends Tree {4 de f depth : I n t = 15 }6 case c l a s s Br ( l : Tree , r : Tree ) extends Tree {7 de f depth : I n t = 1 + ( Math max( l . depth , r . depth ) )8 }9
10 o b j e c t Depth {11
12 de f main ( a r g s : Ar ray [ S t r i n g ] ) =13 p r i n t l n ( (14 Br ( Br ( Lea f ( " a " ) , Br ( Lea f ( "b" ) ,15 Lea f ( " c " ) ) ) , Lea f ( "d" ) ) )16 . depth )17 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Companion Classes
1 a b s t r a c t c l a s s Tree { de f depth : I n t }2
3 c l a s s Lea f ( s : S t r i n g ) extends Tree {4 de f depth : I n t = 15 }6 o b j e c t Lea f { de f app l y ( s : S t r i n g ) = new Lea f ( s ) }7 c l a s s Br ( l : Tree , r : Tree ) extends Tree {8 de f depth : I n t = 1 + ( Math max( l . depth , r . depth ) )9 }10 o b j e c t Br { de f app l y ( l : Tree , r : Tree ) = new Br ( l , r ) }11
12 o b j e c t Depth2 {13
14 de f main ( a r g s : Ar ray [ S t r i n g ] ) =15 p r i n t l n ( (16 Br ( Br ( Lea f ( " a " ) , Br ( Lea f ( "b" ) ,17 Lea f ( " c " ) ) ) , Lea f ( "d" ) ) )18 . depth )19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Companion Classes and Pattern Matching
1 o b j e c t Even { de f unapp ly ( x : I n t ) : Boolean = x % 2 == 0 }2 o b j e c t Odd { de f unapp ly ( x : I n t ) : Boolean = x % 2 != 0 }3 o b j e c t Nega t i v e {4 de f unapp ly ( x : I n t ) : Opt ion [ ( I n t , I n t ) ] =5 i f ( x<0) Some (42 , 23) e l s e None6 }7
8 o b j e c t Companion {9
10 de f main ( a r g s : Ar ray [ S t r i n g ] ) =11 {12 v a l x : I n t = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )13 x match {14 case Negat i v e ( a , b ) => p r i n t l n ( " Answer i s : " + a )15 case Even ( ) => p r i n t l n ( " foo " )16 case Odd ( ) => p r i n t l n ( " bar " )17 }18 }19 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Abstract Types
1 c l a s s Base [U] {2 // type U3 type T = { de f ge t :U }4
5 de f p r i n t ( x :T) = { p r i n t l n ( x . ge t ) }6 }7
8 c l a s s He lpe r { de f ge t = " foo " ; d e f bar = " bar " }9
10 o b j e c t A b s t r a c t {11 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {12 // v a l x = new Base { type U = S t r i n g }13 v a l x = new Base [ S t r i n g ]14 x . p r i n t ( new He lpe r )15 }16 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
List comprehensions
1 > module Main2 > where3 > impor t System ( getArgs )4
5 > permute x = [ ( i , j ) | i <− [ 0 . . x ] , j <− [ i . . x ] ]6
7 > main = do8 > ( x :_) <− getArgs9 > putSt rLn $ show $ permute $ ( ( r ead x ) : : I n t )
10 o b j e c t Comprehend {11 de f permute ( n : I n t ) =12 f o r ( i <− 0 u n t i l n+1; j <− i u n t i l n+1)13 y i e l d P a i r ( i , j )14
15 de f main ( a r g s : Ar ray [ S t r i n g ] ) =16 {17 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )18 p r i n t l n ( permute ( x ) )19 }20 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
List comprehensions
1 > module Main2 > where3 > impor t System ( getArgs )4
5 > permute x = [ ( i , j ) | i <− [ 0 . . x ] , j <− [ i . . x ] ]6
7 > main = do8 > ( x :_) <− getArgs9 > putSt rLn $ show $ permute $ ( ( r ead x ) : : I n t )10 o b j e c t Comprehend {11 de f permute ( n : I n t ) =12 f o r ( i <− 0 u n t i l n+1; j <− i u n t i l n+1)13 y i e l d P a i r ( i , j )14
15 de f main ( a r g s : Ar ray [ S t r i n g ] ) =16 {17 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )18 p r i n t l n ( permute ( x ) )19 }20 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
List comprehensions
1 > module Main2 > where3 > impor t System ( getArgs )4
5 > permute x = [ ( i , j ) | i <− [ 0 . . x ] , j <− [ i . . x ] ,6 ( i+j ) ‘mod ‘ 2 == 0 ]7
8 > main = do9 > ( x :_) <− getArgs10 > putSt rLn $ show $ permute $ ( ( r ead x ) : : I n t )
11 o b j e c t Comprehend2 {12 de f permute ( n : I n t ) =13 f o r ( i <− 0 u n t i l n+1; j <− i u n t i l n+1 i f ( i+j )%2==0)14 y i e l d P a i r ( i , j )15
16 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {17 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )18 p r i n t l n ( permute ( x ) )19 }20 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
List comprehensions
1 > module Main2 > where3 > impor t System ( getArgs )4
5 > permute x = [ ( i , j ) | i <− [ 0 . . x ] , j <− [ i . . x ] ,6 ( i+j ) ‘mod ‘ 2 == 0 ]7
8 > main = do9 > ( x :_) <− getArgs10 > putSt rLn $ show $ permute $ ( ( r ead x ) : : I n t )11 o b j e c t Comprehend2 {12 de f permute ( n : I n t ) =13 f o r ( i <− 0 u n t i l n+1; j <− i u n t i l n+1 i f ( i+j )%2==0)14 y i e l d P a i r ( i , j )15
16 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {17 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )18 p r i n t l n ( permute ( x ) )19 }20 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Lazy evaluation
1 o b j e c t Lazy {2
3 de f bottom : I n t = bottom4
5 de f f 1 ( x : I n t , y : ( ) => I n t ) : I n t = x ∗ 26
7 de f f 2 ( x : I n t , y : => I n t ) : I n t = x ∗ 28
9 de f g ( x : I n t , y : I n t ) : I n t = x ∗ 210
11 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {12 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )13 p r i n t l n ( f 1 ( x , ( ) => bottom ) )14 p r i n t l n ( f 2 ( x , bottom ) )15 }16 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Lazy evaluation
1 c l a s s Foo ( x : I n t ) {2 p r i v a t e de f e x p e n s i v e = x∗x∗x∗x∗x∗x3 p r i v a t e de f compute = {}4
5 l a z y v a l bar = { compute ; e x p e n s i v e }6 }7
8 o b j e c t Lazy2 {9
10 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {11 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )12 v a l f = new Foo ( x )13 i f ( x >42)14 p r i n t l n ( f . bar )15 }16 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Currying
different signature of curried functions (vs. e.g. Haskell)it is possible to convert between curry and non-curryfunctions
Example1 o b j e c t Cur ry {2 de f p l u s ( x : I n t , y : I n t ) = x + y3 de f p l u s 2 ( x : I n t ) ( y : I n t ) = x + y4 de f p l u s 3 ( x : I n t ) = ( y : I n t ) => x+y5
6 v a l p l u s 4 = Funct i on . c u r r i e d ( p l u s _)7
8 v a l f 2 = p l u s 2 (2 ) _9 v a l f 3 = p l u s 3 (2 )10 v a l f 4 = p l u s 4 (2 )11
12 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {13 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )14 p r i n t l n ( f 2 ( x ) ) ; p r i n t l n ( f 3 ( x ) ) ; p r i n t l n ( f 4 ( x ) )15 }16 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Currying
different signature of curried functions (vs. e.g. Haskell)it is possible to convert between curry and non-curryfunctions
Example1 o b j e c t Cur ry {2 de f p l u s ( x : I n t , y : I n t ) = x + y3 de f p l u s 2 ( x : I n t ) ( y : I n t ) = x + y4 de f p l u s 3 ( x : I n t ) = ( y : I n t ) => x+y5
6 v a l p l u s 4 = Funct i on . c u r r i e d ( p l u s _)7
8 v a l f 2 = p l u s 2 (2 ) _9 v a l f 3 = p l u s 3 (2 )10 v a l f 4 = p l u s 4 (2 )11
12 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {13 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )14 p r i n t l n ( f 2 ( x ) ) ; p r i n t l n ( f 3 ( x ) ) ; p r i n t l n ( f 4 ( x ) )15 }16 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Uniform access
to avoid the getter/setter boilerplate hell
Example1 c l a s s FooOld { va r s t a t e : I n t = 0 }2 c l a s s Foo {3 p r i v a t e va r s : I n t = 04 de f s t a t e_ =(x : I n t ) = s = x∗25 de f s t a t e = s6 }7 c l a s s Bar { de f s t a t e : I n t = 23 }8 c l a s s Baz extends Bar { o v e r r i d e v a l s t a t e : I n t = 42 }9
10 o b j e c t Uniform {11 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {12 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )13 va r f = new Foo ; f . s t a t e = x14 p r i n t l n ( f . s t a t e )15 v a l g = new Baz16 p r i n t l n ( g . s t a t e )17 }18 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Uniform access
to avoid the getter/setter boilerplate hell
Example1 c l a s s FooOld { va r s t a t e : I n t = 0 }2 c l a s s Foo {3 p r i v a t e va r s : I n t = 04 de f s t a t e_ =(x : I n t ) = s = x∗25 de f s t a t e = s6 }7 c l a s s Bar { de f s t a t e : I n t = 23 }8 c l a s s Baz extends Bar { o v e r r i d e v a l s t a t e : I n t = 42 }9
10 o b j e c t Uniform {11 de f main ( a r g s : Ar ray [ S t r i n g ] ) = {12 v a l x = I n t e g e r p a r s e I n t ( a r g s ( 0 ) )13 va r f = new Foo ; f . s t a t e = x14 p r i n t l n ( f . s t a t e )15 v a l g = new Baz16 p r i n t l n ( g . s t a t e )17 }18 }
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Actors
Message passing with fancy operatorsSyntax similar to Erlang message passing constructsnot part of the language, a lib with some operators
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Conclusion
Scala fits well into the JVM world→ easy to mix Scala and Java modules
Notation not as elegant as Haskell’sType system limits type inferenceIn comparison to Java many sources oftedious boilerplate are eliminated
ScalaProgrammingLanguage
GeorgSauthoff
Introduction
Features
Conclusion
Discussion
Thanks! && Do you have questions?
ScalaProgrammingLanguage
GeorgSauthoff
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