Known indirect subclasses

A single element contained within a Modifier chain.

Summary

Public functions

foldIn

open fun <R : Any?> foldIn(initial: R, operation: (Modifier.Element, R) -> R): R

Accumulates a value starting with initial and applying operation to the current value and each element from outside in.

Elements wrap one another in a chain from left to right; an Element that appears to the left of another in a + expression or in operation's parameter order affects all of the elements that appear after it. foldIn may be used to accumulate a value starting from the parent or head of the modifier chain to the final wrapped child.

foldOut

open fun <R : Any?> foldOut(initial: R, operation: (Modifier.Element, R) -> R): R

Accumulates a value starting with initial and applying operation to the current value and each element from inside out.

Elements wrap one another in a chain from left to right; an Element that appears to the left of another in a + expression or in operation's parameter order affects all of the elements that appear after it. foldOut may be used to accumulate a value starting from the child or tail of the modifier chain up to the parent or head of the chain.

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Last updated 2026-03-27 UTC.