Are objects immutable in Scala?

An object whose state cannot change after it has been constructed is called immutable (unchangable). The methods of an immutable object do not modify the state of the object. In Scala, all number types, strings, and tuples are immutable. The classes Point, Date, Student, and Card we defined above are all immutable.

What are mutable and immutable objects?

The mutable class examples are StringBuffer, Java. util. Date, StringBuilder, etc. Whereas the immutable objects are legacy classes, wrapper classes, String class, etc….Difference between Mutable and Immutable Objects.

Mutable	Immutable
Mutable classes are may or may not be thread-safe.	Immutable classes are thread-safe.

What is Scala mutable?

Scala collections systematically distinguish between mutable and immutable collections. A mutable collection can be updated or extended in place. This means you can change, add, or remove elements of a collection as a side effect. Immutable collections, by contrast, never change.

What is the difference between mutable and immutable types?

If the value can change, the object is called mutable, while if the value cannot change, the object is called immutable.

What is difference between Singleton and immutable class?

An immutable object is initialized by its constructor only, while a singleton is instantiated by a static method. A set of functions (or static methods) which manipulate some shared mutable state constitute a singleton. A transitively immutable object is NOT a singleton even if globally accessible. It is a constant.

What is mutable variable in Scala?

Mutable Variable: These variables are those variables that allow us to change a value after the declaration of a variable. Mutable variables are defined by using the var keyword. The first letter of data type should be in capital letter because in Scala data type is treated as objects.

What is ::: in Scala?

1. The ::: operator is defined on List trait and concatenates two lists. Using it on Int like in your example ( var a=10 ) shouldn’t work (unless you define such operator yourself).

Is Scala collection map mutable?

Maps are also called Hash tables. There are two kinds of Maps, the immutable and the mutable. The difference between mutable and immutable objects is that when an object is immutable, the object itself can’t be changed. By default, Scala uses the immutable Map.