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Scala Newline Characters Scala is a line-oriented language where statements may be terminated by semicolons (;) or newlines. A semicolon at the end of a statement is usually optional. You can type one if you want but you don't have to if the statement appears by itself on a single line. On the other hand, a semicolon is required if you write multiple statements on a single line. Below syntax is the usage of multiple statements. val s = "hello"; println(s) Scala Packages A package is a named module of code. For example, the Lift utility package is net.liftweb.util. The package declaration is the first non-comment line in the source file as follows: package com.liftcode.stuff Scala packages can be imported so that they can be referenced in the current compilation scope. The following statement imports the contents of the scala.xml package: import scala.xml._ You can import a single class and object, for example, HashMap from the scala.collection.mutable package: import scala.collection.mutable.HashMap You can import more than one class or object from a single package, for example, TreeMap and TreeSet from the scala.collection.immutable package: import scala.collection.immutable.{TreeMap, TreeSet} Apply Dynamic A marker trait that enables dynamic invocations. Instances x of this trait allow method invocations x.meth(args) for arbitrary method names meth and argument lists args as well as field accesses x.field for arbitrary field namesfield. This feature is introduced in Scala-2.10. If a call is not natively supported by x (i.e. if type checking fails), it is rewritten according to the following rules: foo.method("blah") ~~> foo.applyDynamic("method")("blah") 12
Scala foo.method(x = "blah") ~~> foo.applyDynamicNamed("method")(("x", "blah")) foo.method(x = 1, 2) ~~> foo.applyDynamicNamed("method")(("x", 1), ("", 2)) foo.field ~~> foo.selectDynamic("field") foo.varia = 10 ~~> foo.updateDynamic("varia")(10) foo.arr(10) = 13 ~~> foo.selectDynamic("arr").update(10, 13) foo.arr(10) ~~> foo.applyDynamic("arr")(10) 13
Page 2 and 3: Scala About the Tutorial Scala is a
Page 4 and 5: Scala 4. SCALA - DATA .............
Page 6 and 7: Scala Higher-Order Functions ......
Page 8 and 9: Scala Regular-Expression Examples .
Page 10 and 11: Scala Scala can Execute Java Code S
Page 12 and 13: Scala We assume that the readers of
Page 14 and 15: Scala Windows \>scala -version Scal
Page 16 and 17: Scala Welcome to Scala version 2.9.
Page 18 and 19: Scala $salary, 123abc, -salary Oper
Page 22 and 23: 4. SCALA - DATA Scala Scala has all
Page 24 and 25: Scala "Hello,\nWorld!" "This string
Page 26 and 27: 5. SCALA - VARIABLES Scala Variable
Page 28 and 29: Scala } Save the above program in D
Page 30 and 31: Methods Variables 6. SCALA - CLASSE
Page 32 and 33: Scala } Save the above program in D
Page 34 and 35: Scala \>scala Demo Output Point x l
Page 36 and 37: Scala Implicit classes may not be
Page 38 and 39: 7. SCALA - ACCESS MODIFIERS Scala T
Page 40 and 41: Scala } Scope of Protection Access
Page 42 and 43: 8. SCALA - OPERATORS Scala An opera
Page 44 and 45: Scala == (Equal) 1 Checks if the va
Page 46 and 47: Scala It is called Logical AND oper
Page 48 and 49: Scala Ex: (A & B) will give 12, whi
Page 50 and 51: Scala \>scala Demo Output: a & b =
Page 52 and 53: Scala Try the following example pro
Page 54 and 55: Scala c &= a = 0 c ^= a = 10 c |= a
Page 56 and 57: 9. SCALA - IF ELSE STATEMENT Scala
Page 58 and 59: Scala if(Boolean_expression){ //Exe
Page 60 and 61: Scala }else if( x == 30 ){ println(
Page 62 and 63: 10. SCALA - LOOP STATEMENTS Scala T
Page 64 and 65: Scala while(condition) { Conditiona
Page 66 and 67: Scala jumps back up to do, and the
Page 68 and 69: Scala object Demo { } def main(args
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Scala } } Save the above program in
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Scala Scala's for loop allows to fi
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Scala \>scalac Demo.scala \>scala D
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Scala object Demo { def main(args:
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Scala Output: Value of a: 1 Value o
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11. SCALA - FUNCTIONS Scala A funct
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Scala var sum:Int = 0 sum = a + b r
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Scala println("Arg value[" + i + "]
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Scala } Save the above program in D
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Scala logWithDateBound("message3" )
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Scala \>scala Demo Output Factorial
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Scala Currying Functions Currying t
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12. SCALA - CLOSURES Scala A closur
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13. SCALA - STRINGS Scala This chap
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Scala "My name is ".concat("Zara");
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Scala val name = “James” printl
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Scala b String Methods Following is
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Scala 27 28 29 30 31 32 33 34 35 36
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14. SCALA - ARRAYS Scala Scala prov
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Scala } println("Total is " + total
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Scala Save the above program in Dem
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Scala print( " " + x ) } println()
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15. SCALA - COLLECTIONS Scala Scala
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Scala val nums = Nil println( "Head
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Scala 1 2 3 4 5 6 7 8 9 10 11 12 13
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Scala 34 35 36 37 38 39 40 41 42 43
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Scala Find Common Values Insets You
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Scala 14 def diff(that: Set[A]): Se
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Scala 39 def sum: A Returns the sum
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Scala val nums: Map[Int, Int] = Map
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Scala colors.keys.foreach{ i => pri
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Scala 5 def iterator: Iterator[(A,
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Scala 30 def min: (A, B) Finds the
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Scala You can use Tuple to write a
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Scala Concatenated String: (1,hello
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Scala } } Save the above program in
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Scala 2 def isEmpty: Boolean Return
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Scala number of words Find Min & Ma
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Scala 4 def ++[B >: A](that :=> Gen
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Scala 28 def max: A Finds the large
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16. SCALA - TRAITS Scala A trait en
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Scala Value classes and Universal T
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17. SCALA - PATTERN MATCHING Scala
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Scala val charlie = new Person("Cha
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18. SCALA - REGULAR EXPRESSIONNS Sc
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Scala \\n Back-reference to capture
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Scala val pattern = new Regex("abl[
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Scala } } } } Save the above progra
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20. SCALA - EXTRACTORS Scala An ext
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Scala def main(args: Array[String])
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Scala print("Please enter your inpu
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