#[non_exhaustive]pub enum KeyClass {
AsymmetricKeyPair,
PrivateKey,
PublicKey,
SymmetricKey,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against KeyClass
, 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 keyclass = unimplemented!();
match keyclass {
KeyClass::AsymmetricKeyPair => { /* ... */ },
KeyClass::PrivateKey => { /* ... */ },
KeyClass::PublicKey => { /* ... */ },
KeyClass::SymmetricKey => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when keyclass
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant KeyClass::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
KeyClass::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 KeyClass::NewFeature
is defined.
Specifically, when keyclass
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on KeyClass::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
AsymmetricKeyPair
PrivateKey
PublicKey
SymmetricKey
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl Ord for KeyClass
impl Ord for KeyClass
source§impl PartialEq for KeyClass
impl PartialEq for KeyClass
source§impl PartialOrd for KeyClass
impl PartialOrd for KeyClass
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 KeyClass
impl StructuralEq for KeyClass
impl StructuralPartialEq for KeyClass
Auto Trait Implementations§
impl RefUnwindSafe for KeyClass
impl Send for KeyClass
impl Sync for KeyClass
impl Unpin for KeyClass
impl UnwindSafe for KeyClass
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
§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.