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