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