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#getting-started
Title
# getting-started
v

Vampire

05/09/2022, 6:10 PM
Can I formulate
Copy code
fun Provider<out Task>.generateChecksums(destination: Directory? = null) {
    get().generateChecksums(destination)
}

fun Task.generateChecksums(destination: Directory? = null) {
}

fun FileSystemLocation.generateChecksums(destination: Directory? = null) {
}
somehow so that the first one can work for both
Task
or
FileSystemLocation
? Just adding another method does not work of course as both would have the same type-erased form unless I call it differently.
n

nkiesel

05/09/2022, 6:52 PM
Can you add an interface which both
Task
and
FileSystem
implement?
v

Vampire

05/09/2022, 7:15 PM
No
They are 3rd party classes
Best I could come up with while still missing explicit union types is
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fun Provider<out Any>.generateChecksums(destination: Directory? = null) {
    when (val value = get()) {
        is Task -> value.generateChecksums(destination)
        is FileSystemLocation -> value.generateChecksums(destination)
        else -> error("Unsupported Type")
    }
}
but that's bad of course due to the method being callable on all providers. I hoped there is maybe some way using implicit union types.
e

ephemient

05/09/2022, 7:55 PM
Copy code
@JvmName("generateChecksumsTaskProvider")
public fun Provider<out Task>.generateChecksums()

@JvmName("generateChecksumsFileSystemLocationProvider")
public fun Provider<out FileSystemLocation>.generateChecksums()
will both appear as
.generateChecksums()
to Kotlin code
v

Vampire

05/09/2022, 8:00 PM
Ah, nice, thanks. Will try that.
e

ephemient

05/09/2022, 8:56 PM
come to think of it,
TaskProvider<out Task>
wouldn't have any JVM signature conflicts
v

Vampire

05/10/2022, 7:46 AM
How would that help? Then I couldn't call it on
Provider<out Task>
. Besides that there are 5 more types to cover.
e

ephemient

05/10/2022, 8:03 AM
do you really need an extension on
Provider<out Task>
when
tasks.register()
gives you a more specific subtype?
v

Vampire

05/10/2022, 8:06 AM
Yes. And as I said, there are also 5 more types to cover. I just reduced it to two for the question.
Works perfectly fine now with the JvmName trick, thanks again
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