Enum aws_sdk_rum::model::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
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
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<StateEnum> for StateEnum
impl PartialEq<StateEnum> for StateEnum
source§impl PartialOrd<StateEnum> for StateEnum
impl PartialOrd<StateEnum> 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<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.