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