Hi, how to obtain all functions that have a functi...

# reflect

[LeoColman]

Hi, how to obtain all functions that have a functional parameter using Kotlin Reflect?
I tried something like

Class.forName("myClass").declaredMethods.map { it.kotlinFunction!! }.filter { fn -> fn.parameters.any { it is KFunction<*> } }

but it didn't work

[udalov]

Instead of it is KFunction<*> you need to check the parameter's type: it.type.classifier == Function::class

[LeoColman]

That didn't work when I tried it, but I found a solution

[LeoColman]

fun main(args: Array<String>) {
    val funcs = Foo::class.declaredFunctions.filter { func ->
        func.parameters.any { param ->
            param.type.isSubtypeOf(Function::class.starProjectedType)
        }
    }

    println(funcs)
}

class Foo {
    fun <A> foo(fn: (A) -> Unit) {}
    fun <A, B> foo2(fn: (A, B) -> Unit) {}
    fun <A, B, C> foo3(fn: (A, B, C) -> Unit) {}

    fun notThisOne() { }
}

[LeoColman]

@fred.deschenes got it for me in #general