#[non_exhaustive]
pub enum LogDestinationType {
Cloudwatch,
S3,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against LogDestinationType
, 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 logdestinationtype = unimplemented!();
match logdestinationtype {
LogDestinationType::Cloudwatch => { /* ... */ },
LogDestinationType::S3 => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when logdestinationtype
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant LogDestinationType::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
LogDestinationType::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 LogDestinationType::NewFeature
is defined.
Specifically, when logdestinationtype
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on LogDestinationType::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
Cloudwatch
S3
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for LogDestinationType
impl AsRef<str> for LogDestinationType
source§impl Clone for LogDestinationType
impl Clone for LogDestinationType
source§fn clone(&self) -> LogDestinationType
fn clone(&self) -> LogDestinationType
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for LogDestinationType
impl Debug for LogDestinationType
source§impl From<&str> for LogDestinationType
impl From<&str> for LogDestinationType
source§impl FromStr for LogDestinationType
impl FromStr for LogDestinationType
source§impl Hash for LogDestinationType
impl Hash for LogDestinationType
source§impl Ord for LogDestinationType
impl Ord for LogDestinationType
source§fn cmp(&self, other: &LogDestinationType) -> Ordering
fn cmp(&self, other: &LogDestinationType) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq<LogDestinationType> for LogDestinationType
impl PartialEq<LogDestinationType> for LogDestinationType
source§fn eq(&self, other: &LogDestinationType) -> bool
fn eq(&self, other: &LogDestinationType) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<LogDestinationType> for LogDestinationType
impl PartialOrd<LogDestinationType> for LogDestinationType
source§fn partial_cmp(&self, other: &LogDestinationType) -> Option<Ordering>
fn partial_cmp(&self, other: &LogDestinationType) -> 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 LogDestinationType
impl StructuralEq for LogDestinationType
impl StructuralPartialEq for LogDestinationType
Auto Trait Implementations§
impl RefUnwindSafe for LogDestinationType
impl Send for LogDestinationType
impl Sync for LogDestinationType
impl Unpin for LogDestinationType
impl UnwindSafe for LogDestinationType
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.