* the exception is thrown.
     *
     * @param innerSupplier the supplier that produces the inner closeable that is to be safely wrapped
     * @param unsafeWrapper a wrapping function that is potentially unsafe
     * @return the result of the wrapper function
     */
    private
    fun <C : Closeable, T : Closeable> safeWrap(innerSupplier: () -> C, unsafeWrapper: (C) -> T): T {
        // fine if we fail here