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