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