Enum aws_sdk_fsx::types::DriveCacheType
source · #[non_exhaustive]pub enum DriveCacheType {
None,
Read,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against DriveCacheType
, 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 drivecachetype = unimplemented!();
match drivecachetype {
DriveCacheType::None => { /* ... */ },
DriveCacheType::Read => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when drivecachetype
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant DriveCacheType::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
DriveCacheType::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 DriveCacheType::NewFeature
is defined.
Specifically, when drivecachetype
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on DriveCacheType::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
None
Read
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§
source§impl DriveCacheType
impl DriveCacheType
sourcepub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
pub fn try_parse(value: &str) -> Result<Self, UnknownVariantError>
Parses the enum value while disallowing unknown variants.
Unknown variants will result in an error.
Trait Implementations§
source§impl AsRef<str> for DriveCacheType
impl AsRef<str> for DriveCacheType
source§impl Clone for DriveCacheType
impl Clone for DriveCacheType
source§fn clone(&self) -> DriveCacheType
fn clone(&self) -> DriveCacheType
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for DriveCacheType
impl Debug for DriveCacheType
source§impl Display for DriveCacheType
impl Display for DriveCacheType
source§impl From<&str> for DriveCacheType
impl From<&str> for DriveCacheType
source§impl FromStr for DriveCacheType
impl FromStr for DriveCacheType
source§impl Hash for DriveCacheType
impl Hash for DriveCacheType
source§impl Ord for DriveCacheType
impl Ord for DriveCacheType
source§fn cmp(&self, other: &DriveCacheType) -> Ordering
fn cmp(&self, other: &DriveCacheType) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq for DriveCacheType
impl PartialEq for DriveCacheType
source§fn eq(&self, other: &DriveCacheType) -> bool
fn eq(&self, other: &DriveCacheType) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for DriveCacheType
impl PartialOrd for DriveCacheType
source§fn partial_cmp(&self, other: &DriveCacheType) -> Option<Ordering>
fn partial_cmp(&self, other: &DriveCacheType) -> 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 DriveCacheType
impl StructuralPartialEq for DriveCacheType
Auto Trait Implementations§
impl Freeze for DriveCacheType
impl RefUnwindSafe for DriveCacheType
impl Send for DriveCacheType
impl Sync for DriveCacheType
impl Unpin for DriveCacheType
impl UnwindSafe for DriveCacheType
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> 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.