Enum bonsaidb::keystorage::s3::aws_sdk_s3::types::TaggingDirective
pub enum TaggingDirective {
Copy,
Replace,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against TaggingDirective
, 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 taggingdirective = unimplemented!();
match taggingdirective {
TaggingDirective::Copy => { /* ... */ },
TaggingDirective::Replace => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when taggingdirective
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant TaggingDirective::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
TaggingDirective::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 TaggingDirective::NewFeature
is defined.
Specifically, when taggingdirective
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on TaggingDirective::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
Copy
Replace
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
§impl AsRef<str> for TaggingDirective
impl AsRef<str> for TaggingDirective
§impl Clone for TaggingDirective
impl Clone for TaggingDirective
§fn clone(&self) -> TaggingDirective
fn clone(&self) -> TaggingDirective
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read more§impl Debug for TaggingDirective
impl Debug for TaggingDirective
§impl From<&str> for TaggingDirective
impl From<&str> for TaggingDirective
§fn from(s: &str) -> TaggingDirective
fn from(s: &str) -> TaggingDirective
§impl FromStr for TaggingDirective
impl FromStr for TaggingDirective
§type Err = Infallible
type Err = Infallible
§fn from_str(
s: &str
) -> Result<TaggingDirective, <TaggingDirective as FromStr>::Err>
fn from_str( s: &str ) -> Result<TaggingDirective, <TaggingDirective as FromStr>::Err>
s
to return a value of this type. Read more§impl Hash for TaggingDirective
impl Hash for TaggingDirective
§impl Ord for TaggingDirective
impl Ord for TaggingDirective
§fn cmp(&self, other: &TaggingDirective) -> Ordering
fn cmp(&self, other: &TaggingDirective) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
§impl PartialEq<TaggingDirective> for TaggingDirective
impl PartialEq<TaggingDirective> for TaggingDirective
§fn eq(&self, other: &TaggingDirective) -> bool
fn eq(&self, other: &TaggingDirective) -> bool
self
and other
values to be equal, and is used
by ==
.§impl PartialOrd<TaggingDirective> for TaggingDirective
impl PartialOrd<TaggingDirective> for TaggingDirective
§fn partial_cmp(&self, other: &TaggingDirective) -> Option<Ordering>
fn partial_cmp(&self, other: &TaggingDirective) -> 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 TaggingDirective
impl StructuralEq for TaggingDirective
impl StructuralPartialEq for TaggingDirective
Auto Trait Implementations§
impl RefUnwindSafe for TaggingDirective
impl Send for TaggingDirective
impl Sync for TaggingDirective
impl Unpin for TaggingDirective
impl UnwindSafe for TaggingDirective
Blanket Implementations§
§impl<'a, T, E> AsTaggedExplicit<'a, E> for Twhere
T: 'a,
impl<'a, T, E> AsTaggedExplicit<'a, E> for Twhere T: 'a,
§impl<'a, T, E> AsTaggedImplicit<'a, E> for Twhere
T: 'a,
impl<'a, T, E> AsTaggedImplicit<'a, E> for Twhere T: 'a,
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
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.§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.