Is there a more idiomatic way than aborting a loop if needed and returning

null

if it completes?

interface Foo
interface FooProvider { fun provide(): Foo? }

fun provideFoo(providers: List<FooProvider>): Foo? {
	for (provider in providers)
		provider.provide()?.let { return it }

	return null
}

I miss something like

providers.firstNonNullMapped { it.provide() }

(and with a better name).

providers.asSequence().mapNotNull(FooProvider::provide).firstOrNull()

?

That’s one way, yes 🤔 Just a little long and with multiple intermediary objects created.

it’s like three chained method calls, and the sequence operations are optimized pretty well by the compiler

Exactly, also if you don’t like the verbosity of that expression or you need to use it in many places, just encapsulate it in an extension function

that's what I did in a current project. I just wrote my own

mapFirstNotNull

extension method that does the returning loop

asSequence

avoids creating intermediary collections IIRC.