#[non_exhaustive]pub enum EncryptionMethod {
Aes128,
SampleAes,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against EncryptionMethod
, 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 encryptionmethod = unimplemented!();
match encryptionmethod {
EncryptionMethod::Aes128 => { /* ... */ },
EncryptionMethod::SampleAes => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when encryptionmethod
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant EncryptionMethod::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
EncryptionMethod::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 EncryptionMethod::NewFeature
is defined.
Specifically, when encryptionmethod
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on EncryptionMethod::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
Aes128
SampleAes
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 EncryptionMethod
impl EncryptionMethod
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 EncryptionMethod
impl AsRef<str> for EncryptionMethod
source§impl Clone for EncryptionMethod
impl Clone for EncryptionMethod
source§fn clone(&self) -> EncryptionMethod
fn clone(&self) -> EncryptionMethod
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for EncryptionMethod
impl Debug for EncryptionMethod
source§impl Display for EncryptionMethod
impl Display for EncryptionMethod
source§impl From<&str> for EncryptionMethod
impl From<&str> for EncryptionMethod
source§impl FromStr for EncryptionMethod
impl FromStr for EncryptionMethod
source§impl Hash for EncryptionMethod
impl Hash for EncryptionMethod
source§impl Ord for EncryptionMethod
impl Ord for EncryptionMethod
source§fn cmp(&self, other: &EncryptionMethod) -> Ordering
fn cmp(&self, other: &EncryptionMethod) -> 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 EncryptionMethod
impl PartialEq for EncryptionMethod
source§impl PartialOrd for EncryptionMethod
impl PartialOrd for EncryptionMethod
impl Eq for EncryptionMethod
impl StructuralPartialEq for EncryptionMethod
Auto Trait Implementations§
impl Freeze for EncryptionMethod
impl RefUnwindSafe for EncryptionMethod
impl Send for EncryptionMethod
impl Sync for EncryptionMethod
impl Unpin for EncryptionMethod
impl UnwindSafe for EncryptionMethod
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.source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read more