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