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