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threading a question asking about Find Usages (or alternatives) for a function `typealias` or function signature

Our code uses `typealias` for a function signature fairly heavily.  Here is small made-up example:

```data class Widget(val name: String)
typealias PersistWidget = (Widget) -&gt; Boolean

class RealBackend {
    // other functions, not something that can be just a SAM
    fun persist(widget: Widget): Boolean = TODO()
}

class FakeBackend {
    fun persistSuccess(widget: Widget): Boolean = true
    fun persistFailure(widget: Widget): Boolean = false
}

class Facade(val persist: PersistWidget) {
    fun createWidget(): Widget {
        val widget = Widget("default")
        return if (persist(widget)) {
            widget
        } else {
            throw Exception("failed to persist")
        }
    }
}

fun main() {
    val backend = FakeBackend()
    val facade = Facade(backend::persistSuccess)
    facade.createWidget()
}```

If `PersistWidget` were an interface, it'd be easy to find all of the classes that implement that interface

but with a `typealias` I'm not aware of an equivalent ability to find all things that have the same type signature as my `typealias`

is there some way of using Find Usages, or similar, to find all of the things in my code that have the same type signature as the `PersistWidget` typealias?

right now, I can cmd-B on the `PersistWidget` and it'll show me that there is a single use of it in this line:
```class Facade(val persist: PersistWidget) {```
which is correct for explicit usages of that

2020-11-20 at 3.25 PM.png

but I'd also like it to be able to expand that search so that it also shows me functions that are effectively that `typealias` as well, so that it'd show me these too:

I found a sort of similar question in history that seems to imply that it's possible but I haven't figured out how: <https://kotlinlang.slack.com/archives/C0B8H786P/p1585584873009600>

I think it's not possible. Can you please create a feature request at <http://kotl.in/issue> and describe your use case with sample code attached? Thanks!

created: <https://youtrack.jetbrains.com/issue/IDEA-258194>