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