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