#[non_exhaustive]pub enum RdsSavingsEstimationModeSource {
CostExplorerRightsizing,
CostOptimizationHub,
PublicPricing,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against RdsSavingsEstimationModeSource
, 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 rdssavingsestimationmodesource = unimplemented!();
match rdssavingsestimationmodesource {
RdsSavingsEstimationModeSource::CostExplorerRightsizing => { /* ... */ },
RdsSavingsEstimationModeSource::CostOptimizationHub => { /* ... */ },
RdsSavingsEstimationModeSource::PublicPricing => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when rdssavingsestimationmodesource
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant RdsSavingsEstimationModeSource::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
RdsSavingsEstimationModeSource::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 RdsSavingsEstimationModeSource::NewFeature
is defined.
Specifically, when rdssavingsestimationmodesource
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on RdsSavingsEstimationModeSource::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
CostExplorerRightsizing
CostOptimizationHub
PublicPricing
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 RdsSavingsEstimationModeSource
impl RdsSavingsEstimationModeSource
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 RdsSavingsEstimationModeSource
impl AsRef<str> for RdsSavingsEstimationModeSource
source§impl Clone for RdsSavingsEstimationModeSource
impl Clone for RdsSavingsEstimationModeSource
source§fn clone(&self) -> RdsSavingsEstimationModeSource
fn clone(&self) -> RdsSavingsEstimationModeSource
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 RdsSavingsEstimationModeSource
impl From<&str> for RdsSavingsEstimationModeSource
source§impl Ord for RdsSavingsEstimationModeSource
impl Ord for RdsSavingsEstimationModeSource
source§fn cmp(&self, other: &RdsSavingsEstimationModeSource) -> Ordering
fn cmp(&self, other: &RdsSavingsEstimationModeSource) -> 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 RdsSavingsEstimationModeSource
impl PartialEq for RdsSavingsEstimationModeSource
source§fn eq(&self, other: &RdsSavingsEstimationModeSource) -> bool
fn eq(&self, other: &RdsSavingsEstimationModeSource) -> bool
self
and other
values to be equal, and is used by ==
.source§impl PartialOrd for RdsSavingsEstimationModeSource
impl PartialOrd for RdsSavingsEstimationModeSource
impl Eq for RdsSavingsEstimationModeSource
impl StructuralPartialEq for RdsSavingsEstimationModeSource
Auto Trait Implementations§
impl Freeze for RdsSavingsEstimationModeSource
impl RefUnwindSafe for RdsSavingsEstimationModeSource
impl Send for RdsSavingsEstimationModeSource
impl Sync for RdsSavingsEstimationModeSource
impl Unpin for RdsSavingsEstimationModeSource
impl UnwindSafe for RdsSavingsEstimationModeSource
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