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