What is a purpose of Companion Objects in Kotlin?

The purpose of companion objects in Kotlin is to provide a way to define class-level variables and methods, similar to static members in Java and other languages[1][2]. Companion objects allow you to access data and behavior that is tied to a class itself, rather than instances of the class[4].

Some key points about companion objects:

• They are declared using the companion keyword inside a class[1][2]
• Variables and functions defined in a companion object can be accessed using the class name, without needing to create an instance of the class[1][2][4]
• Companion objects are initialized when the class is loaded, similar to static initializers[1]
• They can access private members of the enclosing class[2]
• Companion objects are not the same as singletons in Kotlin. Singletons are created using the object keyword[1].

Companion objects are useful for:

• Defining constants or configuration value...