Kotlin Flow 的 Collect 是否只是内部 kotlinx.coroutines API

Taking the direct example from https://kotlinlang.org/docs/reference/coroutines/flow.html#flows-are-cold

fun simple(): Flow<Int> = flow { 
    println("Flow started")
    for (i in 1..3) {
        delay(100)
        emit(i)
    }
}

fun main() = runBlocking<Unit> {
    println("Calling simple function...")
    val flow = simple()
    println("Calling collect...")
    flow.collect { value -> println(value) } 
    println("Calling collect again...")
    flow.collect { value -> println(value) } 
}

我得到了collect的错误.

This is an internal kotlinx.coroutines API that should not be used from outside of kotlinx.coroutines. No compatibility guarantees are provided.It is recommended to report your use-case of internal API to kotlinx.coroutines issue tracker, so stable API could be provided instead

当我加@InternalCoroutinesApi的时候

@InternalCoroutinesApi
fun main() = runBlocking<Unit> {
    println("Calling simple function...")
    val flow = simple()
    println("Calling collect...")
    flow.collect { value -> println(value) }
    println("Calling collect again...")
    flow.collect { value -> println(value) }
}

I get an error in the collect's lambda (function of value -> println(value) as below

Type mismatch.
Required:
FlowCollector<Int>
Found:
([ERROR :  ]) → Unit
Cannot infer a type for this parameter. Please specify it explicitly.

I am using Kotlin version 1.4.21.

    implementation "org.jetbrains.kotlin:kotlin-stdlib:1.4.2"
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.4.2'
    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.4.1'
    testImplementation 'org.jetbrains.kotlinx:kotlinx-coroutines-test:1.4.2'

我是不是做错了什么，导致我不能在Android Studio中编译示例代码？