#[non_exhaustive]pub enum ConflictExceptionReason {
InvalidRuleState,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against ConflictExceptionReason
, 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 conflictexceptionreason = unimplemented!();
match conflictexceptionreason {
ConflictExceptionReason::InvalidRuleState => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when conflictexceptionreason
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ConflictExceptionReason::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
ConflictExceptionReason::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 ConflictExceptionReason::NewFeature
is defined.
Specifically, when conflictexceptionreason
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on ConflictExceptionReason::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
InvalidRuleState
Unknown(UnknownVariantValue)
Unknown
. See the docs on this enum for the correct way to handle unknown variants.Unknown
contains new variants that have been added since this code was generated.
Implementations§
source§impl ConflictExceptionReason
impl ConflictExceptionReason
sourcepub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
pub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
Parses the enum value while disallowing unknown variants.
Unknown variants will result in an error.
Trait Implementations§
source§impl AsRef<str> for ConflictExceptionReason
impl AsRef<str> for ConflictExceptionReason
source§impl Clone for ConflictExceptionReason
impl Clone for ConflictExceptionReason
source§fn clone(&self) -> ConflictExceptionReason
fn clone(&self) -> ConflictExceptionReason
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for ConflictExceptionReason
impl Debug for ConflictExceptionReason
source§impl From<&str> for ConflictExceptionReason
impl From<&str> for ConflictExceptionReason
source§impl FromStr for ConflictExceptionReason
impl FromStr for ConflictExceptionReason
source§impl Hash for ConflictExceptionReason
impl Hash for ConflictExceptionReason
source§impl Ord for ConflictExceptionReason
impl Ord for ConflictExceptionReason
source§fn cmp(&self, other: &ConflictExceptionReason) -> Ordering
fn cmp(&self, other: &ConflictExceptionReason) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq for ConflictExceptionReason
impl PartialEq for ConflictExceptionReason
source§fn eq(&self, other: &ConflictExceptionReason) -> bool
fn eq(&self, other: &ConflictExceptionReason) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for ConflictExceptionReason
impl PartialOrd for ConflictExceptionReason
source§fn partial_cmp(&self, other: &ConflictExceptionReason) -> Option<Ordering>
fn partial_cmp(&self, other: &ConflictExceptionReason) -> 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 ConflictExceptionReason
impl StructuralEq for ConflictExceptionReason
impl StructuralPartialEq for ConflictExceptionReason
Auto Trait Implementations§
impl RefUnwindSafe for ConflictExceptionReason
impl Send for ConflictExceptionReason
impl Sync for ConflictExceptionReason
impl Unpin for ConflictExceptionReason
impl UnwindSafe for ConflictExceptionReason
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> 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,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§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,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.