How to write lambdas with generics in kotlin?

I can write lambdas id_Int and id_Boolean with explicit type. And I can write function identity with type parameter. Can I write lambdas with type parameter?

fun testFuncInt(f: (Int) -> Int): Int = f(1) + 2

val id_Int = { x: Int -> x }

fun testFuncBoolean(f: (Boolean) -> Boolean): Boolean = !f(false)

val id_Boolean = { x: Boolean -> x }

fun <T> identity(x: T) = x

fun main(args: Array<String>) {
    println(testFuncInt(id_Int))
    println(testFuncInt(::identity))
    println(testFuncBoolean(id_Boolean))
    println(testFuncBoolean(::identity))
}