# Crash in Chapter 6.6

**URL:** <https://forums.kodeco.com/t/crash-in-chapter-6-6/148435>\
**Category:** Data Structures & Algorithms in Swift\
**Created:** [September 21, 2021, 8:07am UTC](https://forums.kodeco.com/t/crash-in-chapter-6-6/148435 "2021-09-21T08:07:07Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![happiehappie](https://assets.chunter.kodeco.com/user_avatar/forums.kodeco.com/happiehappie/32/102075_2.png) [@happiehappie](https://forums.kodeco.com/u/happiehappie)\
**Post date:** [September 21, 2021, 8:07am UTC](https://forums.kodeco.com/t/crash-in-chapter-6-6/148435/1 "2021-09-21T08:07:07Z")

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for end index, it returns tail?.next  
Can anyone confirm if this is intended?  
Using this crash the application as I expected cause tail is already the last node and tail.next is nil