:: does in kotlin

:: in Kotlin is the notation used for creating a reference to a function or property. It is often referred to as the "function reference" or "method reference" operator. There are two main use cases for :: in Kotlin:

1. Reference to a Function: ```kotlin fun exampleFunction(message: String) { println(message) }

val functionReference: (String) -> Unit = ::exampleFunction `` In this example,::exampleFunctioncreates a reference to theexampleFunctionfunction, andfunctionReferenceis a variable that can be used to invokeexampleFunctionwith aString` parameter.

1. Reference to a Property or Member: ```kotlin data class Person(val name: String, val age: Int)

val person = Person("John", 25) val propertyReference: (Person) -> String = Person::name `` Here,Person::namecreates a reference to thenameproperty of thePersonclass.propertyReferenceis a variable that can be used to extract thenameproperty value from aPerson` object.

In summary, :: is used to create references to functions or properties in Kotlin, allowing you to treat them as first-class citizens and pass them around as parameters or store them in variables.