A Tour of Scala - an interactive scala tutorial - Collections Summary

28 Collections Summary - Accessing Elements

As a summary, all collections have a common syntax for accessing elements. Here is a recap

You can access the elements of Arrays, Lists Maps and Sets using ()
For Maps, accessing a key that doesn’t exist throws an exception: java.util.NoSuchElementException: key not found to check if a key exists use map.contains(key) or use a default value: map.getOrElse(key, defaultValue)

val array = Array(1,2,3)   
val list = List(1, 2, 3)  
val map = Map("one" -> 1, "two" -> 2, "three" -> 3)   
val set = Set("a","b","c")  

//Accessing items   
val arrayItem = array(0) //returns item at index 0 which is 1  
val listItem = list(1) //returns item at index 1 which is 2  
val mapItem = map("three") //returns 3  
val setItem = set("a")  //returns true  

println(arrayItem)  
println(listItem)  
println(mapItem)  
println(setItem)

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