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