#[non_exhaustive]pub enum DirectConnectGatewayAssociationProposalState {
Accepted,
Deleted,
Requested,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against DirectConnectGatewayAssociationProposalState, 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 directconnectgatewayassociationproposalstate = unimplemented!();
match directconnectgatewayassociationproposalstate {
DirectConnectGatewayAssociationProposalState::Accepted => { /* ... */ },
DirectConnectGatewayAssociationProposalState::Deleted => { /* ... */ },
DirectConnectGatewayAssociationProposalState::Requested => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when directconnectgatewayassociationproposalstate represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant DirectConnectGatewayAssociationProposalState::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
DirectConnectGatewayAssociationProposalState::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 DirectConnectGatewayAssociationProposalState::NewFeature is defined.
Specifically, when directconnectgatewayassociationproposalstate represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on DirectConnectGatewayAssociationProposalState::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
Accepted
Deleted
Requested
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 DirectConnectGatewayAssociationProposalState
impl DirectConnectGatewayAssociationProposalState
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 Clone for DirectConnectGatewayAssociationProposalState
impl Clone for DirectConnectGatewayAssociationProposalState
source§fn clone(&self) -> DirectConnectGatewayAssociationProposalState
fn clone(&self) -> DirectConnectGatewayAssociationProposalState
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Ord for DirectConnectGatewayAssociationProposalState
impl Ord for DirectConnectGatewayAssociationProposalState
source§fn cmp(&self, other: &DirectConnectGatewayAssociationProposalState) -> Ordering
fn cmp(&self, other: &DirectConnectGatewayAssociationProposalState) -> 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 DirectConnectGatewayAssociationProposalState
impl PartialEq for DirectConnectGatewayAssociationProposalState
source§fn eq(&self, other: &DirectConnectGatewayAssociationProposalState) -> bool
fn eq(&self, other: &DirectConnectGatewayAssociationProposalState) -> bool
self and other values to be equal, and is used
by ==.source§impl PartialOrd for DirectConnectGatewayAssociationProposalState
impl PartialOrd for DirectConnectGatewayAssociationProposalState
source§fn partial_cmp(
&self,
other: &DirectConnectGatewayAssociationProposalState
) -> Option<Ordering>
fn partial_cmp( &self, other: &DirectConnectGatewayAssociationProposalState ) -> 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 DirectConnectGatewayAssociationProposalState
impl StructuralEq for DirectConnectGatewayAssociationProposalState
impl StructuralPartialEq for DirectConnectGatewayAssociationProposalState
Auto Trait Implementations§
impl RefUnwindSafe for DirectConnectGatewayAssociationProposalState
impl Send for DirectConnectGatewayAssociationProposalState
impl Sync for DirectConnectGatewayAssociationProposalState
impl Unpin for DirectConnectGatewayAssociationProposalState
impl UnwindSafe for DirectConnectGatewayAssociationProposalState
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> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§impl<Q, K> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key and return true if they are equal.