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