kotlin-stdlib / kotlin.js / then then JS 1.1 inline fun < T , S > Promise < Promise < T > > . then ( noinline onFulfilled : ( ( T ) -> S ) ? ) : Promise < S > (source) inline fun < T , S > Promise < Promise < T > > . then ( noinline onFulfilled : ( ( T ) -> S ) ? , noinline onRejected : ( ( Throwable ) -> S ) ? ) : Promise < S > (source)