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