```private fun IntArray?.initGroups(offset: Int) {...

# compose

[min]

private fun IntArray?.initGroups(offset: Int) {
    if (this == null) return
    groupNext(0, NULL_ADDRESS)
    groupChild(0, offset)
}

What’s this method for?

internal inline fun IntArray.groupNext(address: GroupAddress, value: Int) {
    this[address + SLOT_TABLE_GROUP_NEXT_OFFSET] = value
}
internal inline fun IntArray.groupChild(address: GroupAddress, value: Int) {
    this[address + SLOT_TABLE_GROUP_CHILD_OFFSET] = value
}

It sets the next address of group 0 to NULL_ADDRESS, effectively marking it as the last group, and… sets the address to its child to offset? What’s the declarative object of these imperative steps?

[Kirill Grouchnikov]

You have the top level comments at https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:compose/runtime/runtime/src/commonMain/kotlin/androidx/compose/runtime/composer/linkbuffer/SlotTableAddresSpace.kt;l=105;bpv=1;bpt=0

You have the CL description in the first commit of this file at https://cs.android.com/androidx/platform/frameworks/support/+/1435417aa61b0fbcc0e64ab49946568011579d2d that points to the previous implementation and multiple alternative explorations of this data structure.

This is about as much as you can get about the internals for this and other similar questions.