Enum aws_sdk_ssm::model::StopType
source · #[non_exhaustive]
pub enum StopType {
Cancel,
Complete,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against StopType, 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 stoptype = unimplemented!();
match stoptype {
StopType::Cancel => { /* ... */ },
StopType::Complete => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when stoptype represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant StopType::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
StopType::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 StopType::NewFeature is defined.
Specifically, when stoptype represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on StopType::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
Cancel
Complete
Unknown(UnknownVariantValue)
Unknown contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl Ord for StopType
impl Ord for StopType
source§impl PartialEq<StopType> for StopType
impl PartialEq<StopType> for StopType
source§impl PartialOrd<StopType> for StopType
impl PartialOrd<StopType> for StopType
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 StopType
impl StructuralEq for StopType
impl StructuralPartialEq for StopType
Auto Trait Implementations§
impl RefUnwindSafe for StopType
impl Send for StopType
impl Sync for StopType
impl Unpin for StopType
impl UnwindSafe for StopType
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.