subSequence 
  Returns a new character sequence that is a subsequence of this character sequence, starting at the specified startIndex and ending right before the specified endIndex.
Since Kotlin
1.0Parameters
startIndex 
the start index (inclusive).
endIndex 
the end index (exclusive).
Returns a new character sequence that is a subsequence of this character sequence, starting at the specified startIndex and ending right before the specified endIndex.
Since Kotlin
1.3Parameters
startIndex 
the start index (inclusive).
endIndex 
the end index (exclusive).