* Also known as "extends-bound" or "upper bound".
     * e.g. `<? extends T>`
     */
    COVARIANT,

    /**
     * Represent a contravariant type argument.
     * Also known as "super-bound" or "lower bound".
     * e.g. `<? super T>`
     */
    CONTRAVARIANT
}


data class ApiFunctionParameter internal constructor(
    internal val index: Int,
    internal val isVarargs: Boolean,