Enum aws_sdk_rum::types::StateEnum
source · #[non_exhaustive]pub enum StateEnum {
Active,
Created,
Deleting,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against StateEnum, 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 stateenum = unimplemented!();
match stateenum {
StateEnum::Active => { /* ... */ },
StateEnum::Created => { /* ... */ },
StateEnum::Deleting => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when stateenum represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant StateEnum::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
StateEnum::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 StateEnum::NewFeature is defined.
Specifically, when stateenum represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on StateEnum::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
Active
Created
Deleting
Unknown(UnknownVariantValue)
Unknown contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl Ord for StateEnum
impl Ord for StateEnum
source§impl PartialEq for StateEnum
impl PartialEq for StateEnum
source§impl PartialOrd for StateEnum
impl PartialOrd for StateEnum
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 StateEnum
impl StructuralEq for StateEnum
impl StructuralPartialEq for StateEnum
Auto Trait Implementations§
impl RefUnwindSafe for StateEnum
impl Send for StateEnum
impl Sync for StateEnum
impl Unpin for StateEnum
impl UnwindSafe for StateEnum
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> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.