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