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