```fun <L, R> left(pair: Pair<L, R>): ...

# getting-started

[min]

fun <L, R> left(pair: Pair<L, R>): L { return pair.first }
fun <L, R> right(pair: Pair<L, R>): R { return pair.second }

pairs.map(::left)

I can do this to transform a List<Pair<A, B>> into a List<A>.

pairs.map(Pair::first)

I’d like to not have to define my own functions however. I’ve tried the following but they all don’t work:
• Pair::first doesn’t compile.
• Pair<*, *>::first compiles but returns a List<*>.
• Pair<VeryLongTypeName, *>::first compiles but is verbose and brittle.
What should I do?

[Alejandro Serrano.Mena]

personally, I would go with pairs.map { it.first } , or even pairs.map { [x, _] -> x }

[CLOVIS]

IntelliJ has a quick-fix to use property reference syntax

[CLOVIS]

But I would also just use pairs.map { it.first }