Extensions on Nullable Types and lateinit Property

Nullable types and extensions

Regular functions cannot be called on nullable variables. However, there is a special kind of function that can be defined such that it can be called on nullable variables. Kotlin stdlib defines the following functions that can be called on String?:

• orEmpty: It returns the value if it is not null. Otherwise, it returns an empty string.

• isNullOrEmpty: It returns true if the value is null or empty. Otherwise, it returns false.

• isNullOrBlank: It returns true if the value is null or blank. Otherwise, it returns false.