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RedundantAsSequence

plugins/kotlin/code-insight/descriptions/resources-en/inspectionDescriptions/RedundantAsSequence.html

2025.3-rc-2583 B
Original Source

Reports redundant asSequence() call that can never have a positive performance effect.

asSequence() speeds up collection processing that includes multiple operations because it performs operations lazily and doesn't create intermediate collections.

However, if a terminal operation (such as toList()) is used right after asSequence(), this doesn't give you any positive performance effect.

Example:

fun test(list: List<String>) {
      list.asSequence().last()
  }

After the quick-fix is applied:

fun test(list: List<String>) {
      list.last()
  }