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