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