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