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