#[non_exhaustive]pub enum ScheduleGroupState {
Active,
Deleting,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against ScheduleGroupState, 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 schedulegroupstate = unimplemented!();
match schedulegroupstate {
ScheduleGroupState::Active => { /* ... */ },
ScheduleGroupState::Deleting => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when schedulegroupstate represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ScheduleGroupState::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
ScheduleGroupState::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 ScheduleGroupState::NewFeature is defined.
Specifically, when schedulegroupstate represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on ScheduleGroupState::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
Active
Deleting
Unknown(UnknownVariantValue)
Unknown contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for ScheduleGroupState
impl AsRef<str> for ScheduleGroupState
source§impl Clone for ScheduleGroupState
impl Clone for ScheduleGroupState
source§fn clone(&self) -> ScheduleGroupState
fn clone(&self) -> ScheduleGroupState
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moresource§impl Debug for ScheduleGroupState
impl Debug for ScheduleGroupState
source§impl From<&str> for ScheduleGroupState
impl From<&str> for ScheduleGroupState
source§impl FromStr for ScheduleGroupState
impl FromStr for ScheduleGroupState
source§impl Hash for ScheduleGroupState
impl Hash for ScheduleGroupState
source§impl Ord for ScheduleGroupState
impl Ord for ScheduleGroupState
source§fn cmp(&self, other: &ScheduleGroupState) -> Ordering
fn cmp(&self, other: &ScheduleGroupState) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<ScheduleGroupState> for ScheduleGroupState
impl PartialEq<ScheduleGroupState> for ScheduleGroupState
source§fn eq(&self, other: &ScheduleGroupState) -> bool
fn eq(&self, other: &ScheduleGroupState) -> bool
self and other values to be equal, and is used
by ==.source§impl PartialOrd<ScheduleGroupState> for ScheduleGroupState
impl PartialOrd<ScheduleGroupState> for ScheduleGroupState
source§fn partial_cmp(&self, other: &ScheduleGroupState) -> Option<Ordering>
fn partial_cmp(&self, other: &ScheduleGroupState) -> 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 ScheduleGroupState
impl StructuralEq for ScheduleGroupState
impl StructuralPartialEq for ScheduleGroupState
Auto Trait Implementations§
impl RefUnwindSafe for ScheduleGroupState
impl Send for ScheduleGroupState
impl Sync for ScheduleGroupState
impl Unpin for ScheduleGroupState
impl UnwindSafe for ScheduleGroupState
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.