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