+/// When handling default_values, we want to map the default-value T directly
+/// to a OptionDeserWrapper<T> in a way that works for `field: T = t;` as
+/// well. Thus, we assume `Into<T> for T` does nothing and use that.
+impl<T: Readable> From<T> for OptionDeserWrapper<T> {
+ fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
+}