Differences

This shows you the differences between two versions of the page.

--- programmiersprachen:scala [2015/10/10 17:00] – [Case classes] phreazer
+++ programmiersprachen:scala [2017/02/19 15:35] – phreazer
@@ Line 1: / Line 1: @@
-Scala
+====== Scala ======
-**Sca**lable **la**nga
-====== Start ======
+**Sca**lable **la**nguage
+===== Start =====
   * No primitive types, everything is an object
@@ Line 12: / Line 14: @@
-===== Hello World =====
+==== Hello World ====
 <code scala>
 object HelloWorld {
@@ Line 21: / Line 23: @@
 </code>
-===== Control structures =====
+==== Control structures ====
 if/else-Constructs have a return value
-==== for loop ====
+=== for loop ===
 <code scala>
 for (i <- 1 to 10) println(i)
 </code>
-==== match ====
+<code scala>
+// different steps
+for (i <- 4 to (17,3)) println(i)
+// other data types than int
+for (s <- myList) println(s)
+// multiple generators
+for (i <- 0 to 2; j <- 3 to 4) println(i+" "+j)
+// filter
+    for {i <- 1 to 6
+         j <- 1 to 6
+         if (i % 2 == 0)
+         if (j % 2 != 0)} println(i+" "+j)
+// yield
+    val list: List[Int] = List(1,2,3,4)
+    val result = for (i <- list) yield i * 2
+    println(result)
+</code>
+=== match ===
 Implizites break
@@ Line 71: / Line 95: @@
 </code>
+==== Inheritance ====
+Scala doesn't support multiple inheritance.
+class B(arg:Int) extends A {}
+Functions can be overridden with overide before func definition.
+Overridding classes, functions or variables can be forbidden with prefix final.
+=== Abstract classes ===
+Difference to Traits: Abstract classes can have constructors. A class which inherits from an abstract class can't inherit from another.
+The usage of override is optional.
+=== Packages object ===
+Objects which are visible in a whole package.
+==== Identity and equality ====
+==-Operator checks equality (identity in Java)
+eq-Operator checks identity
+eq and ne are only defined for clases of type scala.AnyRef.