Enum aws_sdk_elasticache::types::SlaMet
source · #[non_exhaustive]pub enum SlaMet {
Na,
No,
Yes,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against SlaMet
, 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 slamet = unimplemented!();
match slamet {
SlaMet::Na => { /* ... */ },
SlaMet::No => { /* ... */ },
SlaMet::Yes => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when slamet
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant SlaMet::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
SlaMet::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 SlaMet::NewFeature
is defined.
Specifically, when slamet
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on SlaMet::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
Na
No
Yes
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§
Trait Implementations§
source§impl Ord for SlaMet
impl Ord for SlaMet
source§impl PartialEq for SlaMet
impl PartialEq for SlaMet
source§impl PartialOrd for SlaMet
impl PartialOrd for SlaMet
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 SlaMet
impl StructuralEq for SlaMet
impl StructuralPartialEq for SlaMet
Auto Trait Implementations§
impl RefUnwindSafe for SlaMet
impl Send for SlaMet
impl Sync for SlaMet
impl Unpin for SlaMet
impl UnwindSafe for SlaMet
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.