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