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