Hi all, I have a question about kotlin (v1.3.31) r...

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[Lorin]

Hi all, I have a question about kotlin (v1.3.31) reflection.

fun main(args: Array<String>) {
    fun <P1, P2, R> ((P1, P2) -> R).partial(p1: P1): (P2) -> R = { p2: P2 -> this(p1, p2) }

    fun regexMatch(re: Regex, s: String): Boolean = re.containsMatchIn(s)
    val match = ::regexMatch.partial(Regex("^123"))

    println(match("12345"))
    println(match("123xx"))
    println(match("2345"))
    println(match)
    println(match.reflect()!!.run {
        "(${parameters.map { it.type }.joinToString()}) -> $returnType" })
}

The output (the signature of match ) is (P2) -> R.

Is there any way to infer the actual correct signature which should be (String) -> Boolean?

[diesieben07]

Generics are erased at runtime, so in this case the answer is no.
If you can make partial inline you could mark all the type parameters as reified, in which case you can (maybe) get the correct signature.

[Lorin]

inline/reified doesn't help.

[diesieben07]

Then you can't do anything. Why do you need to find out?

[Lorin]

I need to mark down the function signatures to implement dynamic function type casting in kotlin-scripting. It seems that I need figure out a workaround. Thanks!