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