#[non_exhaustive]pub enum ScaleInProtectedInstances {
Ignore,
Refresh,
Wait,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against ScaleInProtectedInstances, 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 scaleinprotectedinstances = unimplemented!();
match scaleinprotectedinstances {
ScaleInProtectedInstances::Ignore => { /* ... */ },
ScaleInProtectedInstances::Refresh => { /* ... */ },
ScaleInProtectedInstances::Wait => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when scaleinprotectedinstances represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ScaleInProtectedInstances::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
ScaleInProtectedInstances::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 ScaleInProtectedInstances::NewFeature is defined.
Specifically, when scaleinprotectedinstances represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on ScaleInProtectedInstances::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
Ignore
Refresh
Wait
Unknown(UnknownVariantValue)
Unknown contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for ScaleInProtectedInstances
impl AsRef<str> for ScaleInProtectedInstances
source§impl Clone for ScaleInProtectedInstances
impl Clone for ScaleInProtectedInstances
source§fn clone(&self) -> ScaleInProtectedInstances
fn clone(&self) -> ScaleInProtectedInstances
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Debug for ScaleInProtectedInstances
impl Debug for ScaleInProtectedInstances
source§impl From<&str> for ScaleInProtectedInstances
impl From<&str> for ScaleInProtectedInstances
source§impl FromStr for ScaleInProtectedInstances
impl FromStr for ScaleInProtectedInstances
source§impl Hash for ScaleInProtectedInstances
impl Hash for ScaleInProtectedInstances
source§impl Ord for ScaleInProtectedInstances
impl Ord for ScaleInProtectedInstances
source§fn cmp(&self, other: &ScaleInProtectedInstances) -> Ordering
fn cmp(&self, other: &ScaleInProtectedInstances) -> 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 ScaleInProtectedInstances
impl PartialEq for ScaleInProtectedInstances
source§fn eq(&self, other: &ScaleInProtectedInstances) -> bool
fn eq(&self, other: &ScaleInProtectedInstances) -> bool
self and other values to be equal, and is used
by ==.source§impl PartialOrd for ScaleInProtectedInstances
impl PartialOrd for ScaleInProtectedInstances
source§fn partial_cmp(&self, other: &ScaleInProtectedInstances) -> Option<Ordering>
fn partial_cmp(&self, other: &ScaleInProtectedInstances) -> Option<Ordering>
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self and other) and is used by the <=
operator. Read moreimpl Eq for ScaleInProtectedInstances
impl StructuralEq for ScaleInProtectedInstances
impl StructuralPartialEq for ScaleInProtectedInstances
Auto Trait Implementations§
impl RefUnwindSafe for ScaleInProtectedInstances
impl Send for ScaleInProtectedInstances
impl Sync for ScaleInProtectedInstances
impl Unpin for ScaleInProtectedInstances
impl UnwindSafe for ScaleInProtectedInstances
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
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.