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