Enum aws_sdk_datasync::types::OverwriteMode
source · #[non_exhaustive]pub enum OverwriteMode {
Always,
Never,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against OverwriteMode
, 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 overwritemode = unimplemented!();
match overwritemode {
OverwriteMode::Always => { /* ... */ },
OverwriteMode::Never => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when overwritemode
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant OverwriteMode::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
OverwriteMode::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 OverwriteMode::NewFeature
is defined.
Specifically, when overwritemode
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on OverwriteMode::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
Always
Never
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 OverwriteMode
impl OverwriteMode
source§impl OverwriteMode
impl OverwriteMode
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 OverwriteMode
impl AsRef<str> for OverwriteMode
source§impl Clone for OverwriteMode
impl Clone for OverwriteMode
source§fn clone(&self) -> OverwriteMode
fn clone(&self) -> OverwriteMode
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for OverwriteMode
impl Debug for OverwriteMode
source§impl From<&str> for OverwriteMode
impl From<&str> for OverwriteMode
source§impl FromStr for OverwriteMode
impl FromStr for OverwriteMode
source§impl Hash for OverwriteMode
impl Hash for OverwriteMode
source§impl Ord for OverwriteMode
impl Ord for OverwriteMode
source§fn cmp(&self, other: &OverwriteMode) -> Ordering
fn cmp(&self, other: &OverwriteMode) -> 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 OverwriteMode
impl PartialEq for OverwriteMode
source§fn eq(&self, other: &OverwriteMode) -> bool
fn eq(&self, other: &OverwriteMode) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for OverwriteMode
impl PartialOrd for OverwriteMode
source§fn partial_cmp(&self, other: &OverwriteMode) -> Option<Ordering>
fn partial_cmp(&self, other: &OverwriteMode) -> 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 OverwriteMode
impl StructuralEq for OverwriteMode
impl StructuralPartialEq for OverwriteMode
Auto Trait Implementations§
impl RefUnwindSafe for OverwriteMode
impl Send for OverwriteMode
impl Sync for OverwriteMode
impl Unpin for OverwriteMode
impl UnwindSafe for OverwriteMode
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.