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