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