kotlinx-coroutines-core/jvm/test/guide/example-flow-28.kt


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/*
 * Copyright 2016-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
 */

// This file was automatically generated from coroutines-guide.md by Knit tool. Do not edit.
package kotlinx.coroutines.guide.flow28

import kotlinx.coroutines.*
import kotlinx.coroutines.flow.*

fun foo(): Flow<String> = 
    flow {
        for (i in 1..3) {
            println("Emitting $i")
            emit(i) // emit next value
        }
    }
    .map { value ->
        check(value <= 1) { "Crashed on $value" }                 
        "string $value"
    }

fun main() = runBlocking<Unit> {
    foo()
        .catch { e -> emit("Caught $e") } // emit on exception
        .collect { value -> println(value) }
}