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kotlinlang

I can't seem to get
```
    suspend operator fun &lt;T&gt; invoke(block: suspend () -&gt; T): T {
        // ...
    }
```

to work. Does `invoke` work with `suspend` keyword?

What errors are you getting? I could do it without problems:
```
    @Test
    fun q() {
        val a = A()
        runBlocking {
            launch {
                val x = a {
                    2
                }
                assertEquals(2, x)
            }.join()
        }
    }
```
```
class A {
    suspend operator fun &lt;Q&gt; invoke(block: suspend () -&gt; Q) : Q{
        delay(2)
        return block()
    }
}
```

Well, something like this:
```
class AsasSuspended: suspend (suspend () -&gt; Int) -&gt; Int {
    override suspend fun invoke(p1: suspend () -&gt; Int): Int {
        TODO("not implemented")
    }
}
```
But I'm getting a `suspend function type is not allowed as supertypes`.

`suspend` is just a modifier, in this case stating you can’t invoke `T` outside of coroutines. I tried an example and seems working fine.

What seems to be problem for you ?

P.S.: Playground example -&gt; <https://play.kotlinlang.org/#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>

<https://youtrack.jetbrains.com/issue/KT-18707>