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