#[non_exhaustive]pub enum ExternalConnectionStatus {
Available,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against ExternalConnectionStatus
, 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 externalconnectionstatus = unimplemented!();
match externalconnectionstatus {
ExternalConnectionStatus::Available => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when externalconnectionstatus
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ExternalConnectionStatus::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
ExternalConnectionStatus::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 ExternalConnectionStatus::NewFeature
is defined.
Specifically, when externalconnectionstatus
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on ExternalConnectionStatus::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
Available
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 ExternalConnectionStatus
impl ExternalConnectionStatus
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 ExternalConnectionStatus
impl AsRef<str> for ExternalConnectionStatus
source§impl Clone for ExternalConnectionStatus
impl Clone for ExternalConnectionStatus
source§fn clone(&self) -> ExternalConnectionStatus
fn clone(&self) -> ExternalConnectionStatus
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for ExternalConnectionStatus
impl Debug for ExternalConnectionStatus
source§impl Display for ExternalConnectionStatus
impl Display for ExternalConnectionStatus
source§impl From<&str> for ExternalConnectionStatus
impl From<&str> for ExternalConnectionStatus
source§impl FromStr for ExternalConnectionStatus
impl FromStr for ExternalConnectionStatus
source§impl Hash for ExternalConnectionStatus
impl Hash for ExternalConnectionStatus
source§impl Ord for ExternalConnectionStatus
impl Ord for ExternalConnectionStatus
source§fn cmp(&self, other: &ExternalConnectionStatus) -> Ordering
fn cmp(&self, other: &ExternalConnectionStatus) -> 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 ExternalConnectionStatus
impl PartialEq for ExternalConnectionStatus
source§fn eq(&self, other: &ExternalConnectionStatus) -> bool
fn eq(&self, other: &ExternalConnectionStatus) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for ExternalConnectionStatus
impl PartialOrd for ExternalConnectionStatus
source§fn partial_cmp(&self, other: &ExternalConnectionStatus) -> Option<Ordering>
fn partial_cmp(&self, other: &ExternalConnectionStatus) -> 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 ExternalConnectionStatus
impl StructuralPartialEq for ExternalConnectionStatus
Auto Trait Implementations§
impl Freeze for ExternalConnectionStatus
impl RefUnwindSafe for ExternalConnectionStatus
impl Send for ExternalConnectionStatus
impl Sync for ExternalConnectionStatus
impl Unpin for ExternalConnectionStatus
impl UnwindSafe for ExternalConnectionStatus
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> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.