#[non_exhaustive]
pub enum NotificationSeverityLevel {
All,
High,
None,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against NotificationSeverityLevel
, 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 notificationseveritylevel = unimplemented!();
match notificationseveritylevel {
NotificationSeverityLevel::All => { /* ... */ },
NotificationSeverityLevel::High => { /* ... */ },
NotificationSeverityLevel::None => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when notificationseveritylevel
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant NotificationSeverityLevel::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
NotificationSeverityLevel::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 NotificationSeverityLevel::NewFeature
is defined.
Specifically, when notificationseveritylevel
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on NotificationSeverityLevel::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
All
High
None
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for NotificationSeverityLevel
impl AsRef<str> for NotificationSeverityLevel
source§impl Clone for NotificationSeverityLevel
impl Clone for NotificationSeverityLevel
source§fn clone(&self) -> NotificationSeverityLevel
fn clone(&self) -> NotificationSeverityLevel
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for NotificationSeverityLevel
impl Debug for NotificationSeverityLevel
source§impl From<&str> for NotificationSeverityLevel
impl From<&str> for NotificationSeverityLevel
source§impl FromStr for NotificationSeverityLevel
impl FromStr for NotificationSeverityLevel
source§impl Hash for NotificationSeverityLevel
impl Hash for NotificationSeverityLevel
source§impl Ord for NotificationSeverityLevel
impl Ord for NotificationSeverityLevel
source§fn cmp(&self, other: &NotificationSeverityLevel) -> Ordering
fn cmp(&self, other: &NotificationSeverityLevel) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
source§impl PartialEq<NotificationSeverityLevel> for NotificationSeverityLevel
impl PartialEq<NotificationSeverityLevel> for NotificationSeverityLevel
source§fn eq(&self, other: &NotificationSeverityLevel) -> bool
fn eq(&self, other: &NotificationSeverityLevel) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<NotificationSeverityLevel> for NotificationSeverityLevel
impl PartialOrd<NotificationSeverityLevel> for NotificationSeverityLevel
source§fn partial_cmp(&self, other: &NotificationSeverityLevel) -> Option<Ordering>
fn partial_cmp(&self, other: &NotificationSeverityLevel) -> 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 NotificationSeverityLevel
impl StructuralEq for NotificationSeverityLevel
impl StructuralPartialEq for NotificationSeverityLevel
Auto Trait Implementations§
impl RefUnwindSafe for NotificationSeverityLevel
impl Send for NotificationSeverityLevel
impl Sync for NotificationSeverityLevel
impl Unpin for NotificationSeverityLevel
impl UnwindSafe for NotificationSeverityLevel
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.