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Use ‘Action’ instead of lambda parameter for compatibility with Kotlin and Gradle

How can I do it, if I want to add a lambda configuration on `RepositoryHandler`?

Like this, following the same pattern as the Gradle code.
```fun RepositoryHandler.github(action: Action&lt;GithubArtifactRepository&gt;) { .. action.execute(..) .. }```


From a caller perspective it’s the same: `github { … }` , and the same for Kotlin or Groovy DSLs.

and how do you encode the return value? (In my case is `Unit`, but what about other types?)

The method returns the desired value, such as:
```fun RepositoryHandler.github(action: Action&lt;GithubArtifactRepository&gt;) : String { .. action.execute(..) .. }```


`Action` itself doesn’t have a return value, by design, as it’s intended to configure other objects.

example:
```
public fun ConfigurationContainer.createResolvable(
    name: String,
    action: Action&lt;Configuration&gt; = Action {}
): Configuration {
    var configuration = findByName(name)
    if (configuration == null) {
        configuration = create(name) {
            isCanBeConsumed = false
            isCanBeResolved = true
            isVisible = false
            action.execute(this)
        }
    }
    return configuration
}```

ok, next step now
```fun PublicationContainer.createGithubPublication(name: String = "maven",
                                                 block: MavenPublication.() -&gt; Unit) {
    currentSnapshot = null
    create(name, block)
    currentSnapshot?.let {
        create(it.name, block).version = it.version
        currentSnapshot = null
    }
}```
`create` does accept a `String, Action&lt;in Publication&gt;`, however if I switch to
```fun PublicationContainer.createGithubPublication(name: String = "maven",
                                                 action: Action&lt;MavenPublication&gt;) {
    currentSnapshot = null
    create(name, action)```
then `create` turns red
&gt; None of the following functions can be called with the arguments supplied.


take in account that `MavenPublication extends Publication`

use this variant:
``` &lt;U extends T&gt; U create(String name, Class&lt;U&gt; type, Action&lt;? super U&gt; configuration) throws InvalidUserDataException;```

you need to provide the class of object to create

or use this from org.gradle.kotlin.dsl:
```create&lt;MavenPublication&gt;("javaLibrary")```

```create&lt;MavenPublication&gt;("javaLibrary") {
   action.execute(this)
}```


thanks Chris, that seemed to make the compiler happy