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