| /* |
| * Copyright 2016-2017 JetBrains s.r.o. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| // This file was automatically generated from coroutines-guide.md by Knit tool. Do not edit. |
| package guide.select.example02 |
| |
| import kotlinx.coroutines.experimental.* |
| import kotlinx.coroutines.experimental.channels.* |
| import kotlinx.coroutines.experimental.selects.* |
| |
| suspend fun selectAorB(a: ReceiveChannel<String>, b: ReceiveChannel<String>): String = |
| select<String> { |
| a.onReceiveOrNull { value -> |
| if (value == null) |
| "Channel 'a' is closed" |
| else |
| "a -> '$value'" |
| } |
| b.onReceiveOrNull { value -> |
| if (value == null) |
| "Channel 'b' is closed" |
| else |
| "b -> '$value'" |
| } |
| } |
| |
| fun main(args: Array<String>) = runBlocking<Unit> { |
| // we are using the context of the main thread in this example for predictability ... |
| val a = produce<String>(coroutineContext) { |
| repeat(4) { send("Hello $it") } |
| } |
| val b = produce<String>(coroutineContext) { |
| repeat(4) { send("World $it") } |
| } |
| repeat(8) { // print first eight results |
| println(selectAorB(a, b)) |
| } |
| coroutineContext.cancelChildren() |
| } |