#[non_exhaustive]pub enum SearchableQueueType {
Standard,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against SearchableQueueType
, 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 searchablequeuetype = unimplemented!();
match searchablequeuetype {
SearchableQueueType::Standard => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when searchablequeuetype
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant SearchableQueueType::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
SearchableQueueType::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 SearchableQueueType::NewFeature
is defined.
Specifically, when searchablequeuetype
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on SearchableQueueType::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
Standard
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for SearchableQueueType
impl AsRef<str> for SearchableQueueType
source§impl Clone for SearchableQueueType
impl Clone for SearchableQueueType
source§fn clone(&self) -> SearchableQueueType
fn clone(&self) -> SearchableQueueType
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for SearchableQueueType
impl Debug for SearchableQueueType
source§impl From<&str> for SearchableQueueType
impl From<&str> for SearchableQueueType
source§impl FromStr for SearchableQueueType
impl FromStr for SearchableQueueType
source§impl Hash for SearchableQueueType
impl Hash for SearchableQueueType
source§impl Ord for SearchableQueueType
impl Ord for SearchableQueueType
source§fn cmp(&self, other: &SearchableQueueType) -> Ordering
fn cmp(&self, other: &SearchableQueueType) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<SearchableQueueType> for SearchableQueueType
impl PartialEq<SearchableQueueType> for SearchableQueueType
source§fn eq(&self, other: &SearchableQueueType) -> bool
fn eq(&self, other: &SearchableQueueType) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<SearchableQueueType> for SearchableQueueType
impl PartialOrd<SearchableQueueType> for SearchableQueueType
source§fn partial_cmp(&self, other: &SearchableQueueType) -> Option<Ordering>
fn partial_cmp(&self, other: &SearchableQueueType) -> 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 SearchableQueueType
impl StructuralEq for SearchableQueueType
impl StructuralPartialEq for SearchableQueueType
Auto Trait Implementations§
impl RefUnwindSafe for SearchableQueueType
impl Send for SearchableQueueType
impl Sync for SearchableQueueType
impl Unpin for SearchableQueueType
impl UnwindSafe for SearchableQueueType
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<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.