Reified type parameters through inline constructors

Language Design
6

IMHO this can be solved in most cases with either:

  • a “companion” inline function, with the same name as the class, when the type parameter is to be chosen by the user (Foo)
  • a constant argument, when the type parameter is fixed by the subclass (StringFoo)
@Suppress("FunctionName")
inline fun <reified T> Foo() = Foo(T::class.java)

open class Foo<T>(private val type: Class<T>) {
  val name: String get() = type.name
  fun newInstance(): T = type.newInstance()
}

class StringFoo : Foo<String>(String::class.java)

fun main() {
    println(Foo<Int>().name)   // java.lang.Integer
    println(StringFoo().name)  // java.lang.String
}
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