isEmpty 
  Returns true if the collection is empty (contains no elements), false otherwise.
Since Kotlin
1.0Returns true if the collection is empty (contains no elements), false otherwise.
Since Kotlin
1.1Returns true if the collection is empty (contains no elements), false otherwise.
Since Kotlin
1.0Returns true if the collection is empty (contains no elements), false otherwise.
Since Kotlin
1.3Returns true if the collection is empty (contains no elements), false otherwise.