#[non_exhaustive]pub enum OptionalObjectAttributes {
RestoreStatus,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against OptionalObjectAttributes
, it is important to ensure
your code is forward-compatible. That is, if a match arm handles a case for a
feature that is supported by the service but has not been represented as an enum
variant in a current version of SDK, your code should continue to work when you
upgrade SDK to a future version in which the enum does include a variant for that
feature.
Here is an example of how you can make a match expression forward-compatible:
# let optionalobjectattributes = unimplemented!();
match optionalobjectattributes {
OptionalObjectAttributes::RestoreStatus => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when optionalobjectattributes
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant OptionalObjectAttributes::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
OptionalObjectAttributes::Unknown(UnknownVariantValue("NewFeature".to_owned()))
and calling as_str
on it yields "NewFeature"
.
This match expression is forward-compatible when executed with a newer
version of SDK where the variant OptionalObjectAttributes::NewFeature
is defined.
Specifically, when optionalobjectattributes
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on OptionalObjectAttributes::NewFeature
also yielding "NewFeature"
.
Explicitly matching on the Unknown
variant should
be avoided for two reasons:
- The inner data
UnknownVariantValue
is opaque, and no further information can be extracted. - It might inadvertently shadow other intended match arms.
Variants (Non-exhaustive)§
This enum is marked as non-exhaustive
RestoreStatus
Unknown(UnknownVariantValue)
Unknown
. See the docs on this enum for the correct way to handle unknown variants.Unknown
contains new variants that have been added since this code was generated.
Implementations§
source§impl OptionalObjectAttributes
impl OptionalObjectAttributes
sourcepub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
pub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
Parses the enum value while disallowing unknown variants.
Unknown variants will result in an error.
Trait Implementations§
source§impl AsRef<str> for OptionalObjectAttributes
impl AsRef<str> for OptionalObjectAttributes
source§impl Clone for OptionalObjectAttributes
impl Clone for OptionalObjectAttributes
source§fn clone(&self) -> OptionalObjectAttributes
fn clone(&self) -> OptionalObjectAttributes
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for OptionalObjectAttributes
impl Debug for OptionalObjectAttributes
source§impl Display for OptionalObjectAttributes
impl Display for OptionalObjectAttributes
source§impl From<&str> for OptionalObjectAttributes
impl From<&str> for OptionalObjectAttributes
source§impl FromStr for OptionalObjectAttributes
impl FromStr for OptionalObjectAttributes
source§impl Hash for OptionalObjectAttributes
impl Hash for OptionalObjectAttributes
source§impl Ord for OptionalObjectAttributes
impl Ord for OptionalObjectAttributes
source§fn cmp(&self, other: &OptionalObjectAttributes) -> Ordering
fn cmp(&self, other: &OptionalObjectAttributes) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq for OptionalObjectAttributes
impl PartialEq for OptionalObjectAttributes
source§impl PartialOrd for OptionalObjectAttributes
impl PartialOrd for OptionalObjectAttributes
impl Eq for OptionalObjectAttributes
impl StructuralPartialEq for OptionalObjectAttributes
Auto Trait Implementations§
impl Freeze for OptionalObjectAttributes
impl RefUnwindSafe for OptionalObjectAttributes
impl Send for OptionalObjectAttributes
impl Sync for OptionalObjectAttributes
impl Unpin for OptionalObjectAttributes
impl UnwindSafe for OptionalObjectAttributes
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)source§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.