# Simpler Coroutine Scope Creation
**URL:** https://discuss.kotlinlang.org/t/simpler-coroutine-scope-creation/10833
**Category:** Language Design
**Created:** [December 19, 2018, 2:29pm UTC](https://discuss.kotlinlang.org/t/simpler-coroutine-scope-creation/10833 "2018-12-19T14:29:51Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@gesh](https://discuss.kotlinlang.org/u/gesh)
#### Post date: [December 19, 2018, 2:29pm UTC](https://discuss.kotlinlang.org/t/simpler-coroutine-scope-creation/10833/1 "2018-12-19T14:29:51Z")
I’ve been migrating some code from the experimental coroutines to the release version and I find I have to add the same few lines of code to most my classes that spawn new coroutines to make them all CoroutineScoped.
It goes something like this:
```kotlin
class ExampleBefore : CoroutineScope {
private val job = Job()
override val coroutineContext: CoroutineContext get() = job + Dispatchers.IO
}
```
Or another dispatcher depending on the class’ needs.
Since I’m lazy and hate duplicating this code around I made myself a new interface for this and a default implementation intended for use as a delegate implementation of the scope interface.
```kotlin
import kotlinx.coroutines.CoroutineDispatcher
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Job
import kotlin.coroutines.CoroutineContext
interface CoroutineScopeAndJob : CoroutineScope {
val job: Job
}
class JobBasedScope(val dispatcher: CoroutineDispatcher) : CoroutineScopeAndJob {
override val job = Job()
override val coroutineContext: CoroutineContext get() = job + dispatcher
}
```
Now in order to make a class able to spawn coroutines in it’s own tree of jobs for easier cancellation I can just delegate the interface to the implementation in a single line like this:
```kotlin
class ExampleAfter : CoroutineScopeAndJob by JobBasedScope(Dispatchers.IO)
```
Works like a charm, so I thought I’ll share it here for anyone else migrating.
Oh I also made a git gist of it all:
>
---
### Author:  [@benjaminhill](https://discuss.kotlinlang.org/u/benjaminhill)
#### Post date: [March 9, 2019, 11:52pm UTC](https://discuss.kotlinlang.org/t/simpler-coroutine-scope-creation/10833/2 "2019-03-09T23:52:27Z")
Question: would it make any sense to extend to be AutoClosable? Or is that redundant with what a “Coroutine Scope” is?
```
// from https://gist.github.com/markov/36f197a8cab2072750e99d976104670a
// class ExampleAfter : CoroutineScopeAndJob by JobBasedScope
interface CoroutineScopeAndJob : CoroutineScope, AutoCloseable {
val job: Job
}
class JobBasedScope : CoroutineScopeAndJob {
override val job = Job()
override val coroutineContext: CoroutineContext get() = job + Dispatchers.Default
override fun close() {
job.cancel()
}
}
```