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JavaScript Reflection

In Kotlin compiled to JavaScript, there's a property available on any object called jsClass which returns a JsClass instance. JsClass currently can do nothing more than providing a (non-qualified) name of the class. However, the JsClass instance itself is a reference to the constructor function. This can be used to interoperate with JS functions that expect a reference to a constructor.

To get a reference to a class, you can use the ::class syntax. Full reflection API is currently not supported in Kotlin for JavaScript; the only available properties are .simpleName which returns the name of the class and .js which returns the corresponding JsClass.

Examples:

class A
class B
class C

inline fun <reified T> foo() {
    println(jsClass<T>().name)
}

println(A().jsClass.name)     // prints "A"
println(B::class.simpleName)  // prints "B"
println(B::class.js.name)     // prints "B"
foo<C>()                      // prints "C"