#[non_exhaustive]pub enum DataSourceLevelMetricsBehavior {
FullRequestDataSourceMetrics,
PerDataSourceMetrics,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against DataSourceLevelMetricsBehavior
, 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 datasourcelevelmetricsbehavior = unimplemented!();
match datasourcelevelmetricsbehavior {
DataSourceLevelMetricsBehavior::FullRequestDataSourceMetrics => { /* ... */ },
DataSourceLevelMetricsBehavior::PerDataSourceMetrics => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when datasourcelevelmetricsbehavior
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant DataSourceLevelMetricsBehavior::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
DataSourceLevelMetricsBehavior::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 DataSourceLevelMetricsBehavior::NewFeature
is defined.
Specifically, when datasourcelevelmetricsbehavior
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on DataSourceLevelMetricsBehavior::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
FullRequestDataSourceMetrics
PerDataSourceMetrics
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 DataSourceLevelMetricsBehavior
impl DataSourceLevelMetricsBehavior
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 DataSourceLevelMetricsBehavior
impl AsRef<str> for DataSourceLevelMetricsBehavior
source§impl Clone for DataSourceLevelMetricsBehavior
impl Clone for DataSourceLevelMetricsBehavior
source§fn clone(&self) -> DataSourceLevelMetricsBehavior
fn clone(&self) -> DataSourceLevelMetricsBehavior
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl From<&str> for DataSourceLevelMetricsBehavior
impl From<&str> for DataSourceLevelMetricsBehavior
source§impl Ord for DataSourceLevelMetricsBehavior
impl Ord for DataSourceLevelMetricsBehavior
source§fn cmp(&self, other: &DataSourceLevelMetricsBehavior) -> Ordering
fn cmp(&self, other: &DataSourceLevelMetricsBehavior) -> 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 DataSourceLevelMetricsBehavior
impl PartialEq for DataSourceLevelMetricsBehavior
source§fn eq(&self, other: &DataSourceLevelMetricsBehavior) -> bool
fn eq(&self, other: &DataSourceLevelMetricsBehavior) -> bool
self
and other
values to be equal, and is used by ==
.source§impl PartialOrd for DataSourceLevelMetricsBehavior
impl PartialOrd for DataSourceLevelMetricsBehavior
impl Eq for DataSourceLevelMetricsBehavior
impl StructuralPartialEq for DataSourceLevelMetricsBehavior
Auto Trait Implementations§
impl Freeze for DataSourceLevelMetricsBehavior
impl RefUnwindSafe for DataSourceLevelMetricsBehavior
impl Send for DataSourceLevelMetricsBehavior
impl Sync for DataSourceLevelMetricsBehavior
impl Unpin for DataSourceLevelMetricsBehavior
impl UnwindSafe for DataSourceLevelMetricsBehavior
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
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)source§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read more