#[non_exhaustive]pub enum RotationType {
Automatic,
OnDemand,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against RotationType, 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 rotationtype = unimplemented!();
match rotationtype {
RotationType::Automatic => { /* ... */ },
RotationType::OnDemand => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}The above code demonstrates that when rotationtype represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant RotationType::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
RotationType::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 RotationType::NewFeature is defined.
Specifically, when rotationtype represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on RotationType::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
Automatic
OnDemand
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 RotationType
impl RotationType
Source§impl RotationType
impl RotationType
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 RotationType
impl AsRef<str> for RotationType
Source§impl Clone for RotationType
impl Clone for RotationType
Source§fn clone(&self) -> RotationType
fn clone(&self) -> RotationType
1.0.0 · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moreSource§impl Debug for RotationType
impl Debug for RotationType
Source§impl Display for RotationType
impl Display for RotationType
Source§impl From<&str> for RotationType
impl From<&str> for RotationType
Source§impl FromStr for RotationType
impl FromStr for RotationType
Source§impl Hash for RotationType
impl Hash for RotationType
Source§impl Ord for RotationType
impl Ord for RotationType
Source§fn cmp(&self, other: &RotationType) -> Ordering
fn cmp(&self, other: &RotationType) -> 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 RotationType
impl PartialEq for RotationType
Source§impl PartialOrd for RotationType
impl PartialOrd for RotationType
impl Eq for RotationType
impl StructuralPartialEq for RotationType
Auto Trait Implementations§
impl Freeze for RotationType
impl RefUnwindSafe for RotationType
impl Send for RotationType
impl Sync for RotationType
impl Unpin for RotationType
impl UnwindSafe for RotationType
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§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§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.Source§impl<T> Instrument for T
impl<T> Instrument for T
Source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
Source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
Source§impl<T> IntoEither for T
impl<T> IntoEither for T
Source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left is true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read moreSource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self into a Left variant of Either<Self, Self>
if into_left(&self) returns true.
Converts self into a Right variant of Either<Self, Self>
otherwise. Read more