Enum aws_sdk_s3::types::Tier
source · #[non_exhaustive]pub enum Tier {
Bulk,
Expedited,
Standard,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against Tier
, 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 tier = unimplemented!();
match tier {
Tier::Bulk => { /* ... */ },
Tier::Expedited => { /* ... */ },
Tier::Standard => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when tier
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant Tier::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
Tier::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 Tier::NewFeature
is defined.
Specifically, when tier
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on Tier::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
Bulk
Expedited
Standard
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 Tier
impl Ord for Tier
source§impl PartialOrd for Tier
impl PartialOrd for Tier
impl Eq for Tier
impl StructuralPartialEq for Tier
Auto Trait Implementations§
impl Freeze for Tier
impl RefUnwindSafe for Tier
impl Send for Tier
impl Sync for Tier
impl Unpin for Tier
impl UnwindSafe for Tier
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<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)source§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.