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