Try It Yourself - SyntaxStudy Editor

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

fun numberFlow(): Flow<Int> = flow {
    println("Flow started")
    for (i in 1..5) {
        delay(100)
        emit(i)
    }
}

fun main() = runBlocking {
    // Basic collection
    numberFlow()
        .map     { it * it }
        .filter  { it > 5 }
        .collect { println("Received: $it") }

println()

// flowOf and asFlow
    flowOf("a", "b", "c").collect { print("$it ") }
    println()
    (1..3).asFlow().collect { print("$it ") }
    println()

// transform — emit multiple values per upstream item
    (1..3).asFlow()
        .transform { n ->
            emit("before $n")
            emit(n * 10)
        }
        .collect { println(it) }

// StateFlow
    val stateFlow = MutableStateFlow(0)
    val job = launch {
        stateFlow.collect { println("State: $it") }
    }
    stateFlow.value = 1
    stateFlow.value = 2
    delay(100)
    job.cancel()

// zip two flows
    val flow1 = flowOf("One", "Two", "Three")
    val flow2 = flowOf(1, 2, 3)
    flow1.zip(flow2) { s, n -> "$s=$n" }.collect { println(it) }
}