W3cubDocs

/Kotlin

indexOf

Platform and version requirements:
fun indexOf(element: @UnsafeVariance E): Int
Platform and version requirements: JS (1.1)
open fun indexOf(element: E): Int
Platform and version requirements: Native (1.3)
fun indexOf(element: E): Int

Returns the index of the first occurrence of the specified element in the list, or -1 if the specified element is not contained in the list.

© 2010–2020 JetBrains s.r.o. and Kotlin Programming Language contributors
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-array-list/index-of.html