propertyNames.mapNotNull { propertyName ->
        stringPropertyOrNull(propertyName)?.let { propertyValue ->
            propertyName to propertyValue
        }
    }.toMap()


/**
 * Creates a [Provider] that returns `true` when this [Provider] has a value
 * and `false` otherwise. The returned [Provider] always has a value.
 * @see Provider.isPresent
 */
private