Enum aws_sdk_ec2::types::MonitoringState
source · #[non_exhaustive]pub enum MonitoringState {
Disabled,
Disabling,
Enabled,
Pending,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against MonitoringState
, 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 monitoringstate = unimplemented!();
match monitoringstate {
MonitoringState::Disabled => { /* ... */ },
MonitoringState::Disabling => { /* ... */ },
MonitoringState::Enabled => { /* ... */ },
MonitoringState::Pending => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when monitoringstate
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant MonitoringState::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
MonitoringState::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 MonitoringState::NewFeature
is defined.
Specifically, when monitoringstate
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on MonitoringState::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
Disabled
Disabling
Enabled
Pending
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for MonitoringState
impl AsRef<str> for MonitoringState
source§impl Clone for MonitoringState
impl Clone for MonitoringState
source§fn clone(&self) -> MonitoringState
fn clone(&self) -> MonitoringState
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for MonitoringState
impl Debug for MonitoringState
source§impl From<&str> for MonitoringState
impl From<&str> for MonitoringState
source§impl FromStr for MonitoringState
impl FromStr for MonitoringState
source§impl Hash for MonitoringState
impl Hash for MonitoringState
source§impl Ord for MonitoringState
impl Ord for MonitoringState
source§fn cmp(&self, other: &MonitoringState) -> Ordering
fn cmp(&self, other: &MonitoringState) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<MonitoringState> for MonitoringState
impl PartialEq<MonitoringState> for MonitoringState
source§fn eq(&self, other: &MonitoringState) -> bool
fn eq(&self, other: &MonitoringState) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<MonitoringState> for MonitoringState
impl PartialOrd<MonitoringState> for MonitoringState
source§fn partial_cmp(&self, other: &MonitoringState) -> Option<Ordering>
fn partial_cmp(&self, other: &MonitoringState) -> 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 MonitoringState
impl StructuralEq for MonitoringState
impl StructuralPartialEq for MonitoringState
Auto Trait Implementations§
impl RefUnwindSafe for MonitoringState
impl Send for MonitoringState
impl Sync for MonitoringState
impl Unpin for MonitoringState
impl UnwindSafe for MonitoringState
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> Equivalent<K> for Qwhere
Q: Eq + ?Sized,
K: Borrow<Q> + ?Sized,
impl<Q, K> Equivalent<K> for Qwhere Q: Eq + ?Sized, K: Borrow<Q> + ?Sized,
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.