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