Enum aws_sdk_ec2::types::TargetStorageTier
source · #[non_exhaustive]pub enum TargetStorageTier {
Archive,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against TargetStorageTier
, 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 targetstoragetier = unimplemented!();
match targetstoragetier {
TargetStorageTier::Archive => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when targetstoragetier
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant TargetStorageTier::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
TargetStorageTier::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 TargetStorageTier::NewFeature
is defined.
Specifically, when targetstoragetier
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on TargetStorageTier::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
Archive
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for TargetStorageTier
impl AsRef<str> for TargetStorageTier
source§impl Clone for TargetStorageTier
impl Clone for TargetStorageTier
source§fn clone(&self) -> TargetStorageTier
fn clone(&self) -> TargetStorageTier
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for TargetStorageTier
impl Debug for TargetStorageTier
source§impl From<&str> for TargetStorageTier
impl From<&str> for TargetStorageTier
source§impl FromStr for TargetStorageTier
impl FromStr for TargetStorageTier
source§impl Hash for TargetStorageTier
impl Hash for TargetStorageTier
source§impl Ord for TargetStorageTier
impl Ord for TargetStorageTier
source§fn cmp(&self, other: &TargetStorageTier) -> Ordering
fn cmp(&self, other: &TargetStorageTier) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<TargetStorageTier> for TargetStorageTier
impl PartialEq<TargetStorageTier> for TargetStorageTier
source§fn eq(&self, other: &TargetStorageTier) -> bool
fn eq(&self, other: &TargetStorageTier) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<TargetStorageTier> for TargetStorageTier
impl PartialOrd<TargetStorageTier> for TargetStorageTier
source§fn partial_cmp(&self, other: &TargetStorageTier) -> Option<Ordering>
fn partial_cmp(&self, other: &TargetStorageTier) -> 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 TargetStorageTier
impl StructuralEq for TargetStorageTier
impl StructuralPartialEq for TargetStorageTier
Auto Trait Implementations§
impl RefUnwindSafe for TargetStorageTier
impl Send for TargetStorageTier
impl Sync for TargetStorageTier
impl Unpin for TargetStorageTier
impl UnwindSafe for TargetStorageTier
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.