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