arrow-optics / arrow.optics / PTraversal / foldMap
open fun <R> foldMap(M: Monoid<R>, s: S, f: (A) -> R): R open fun <R> foldMap(s: S, f: (A) -> R, M: Monoid<R>): R
open fun <R> foldMap(M: Monoid<R>, s: S, f: (A) -> R): R
open fun <R> foldMap(s: S, f: (A) -> R, M: Monoid<R>): R
Map each target to a Monoid and combine the results
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