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