Enum aws_sdk_lambda::types::SnapStartApplyOn
source · #[non_exhaustive]pub enum SnapStartApplyOn {
None,
PublishedVersions,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against SnapStartApplyOn
, 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 snapstartapplyon = unimplemented!();
match snapstartapplyon {
SnapStartApplyOn::None => { /* ... */ },
SnapStartApplyOn::PublishedVersions => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when snapstartapplyon
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant SnapStartApplyOn::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
SnapStartApplyOn::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 SnapStartApplyOn::NewFeature
is defined.
Specifically, when snapstartapplyon
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on SnapStartApplyOn::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
None
PublishedVersions
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 SnapStartApplyOn
impl SnapStartApplyOn
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 SnapStartApplyOn
impl AsRef<str> for SnapStartApplyOn
source§impl Clone for SnapStartApplyOn
impl Clone for SnapStartApplyOn
source§fn clone(&self) -> SnapStartApplyOn
fn clone(&self) -> SnapStartApplyOn
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for SnapStartApplyOn
impl Debug for SnapStartApplyOn
source§impl Display for SnapStartApplyOn
impl Display for SnapStartApplyOn
source§impl From<&str> for SnapStartApplyOn
impl From<&str> for SnapStartApplyOn
source§impl FromStr for SnapStartApplyOn
impl FromStr for SnapStartApplyOn
source§impl Hash for SnapStartApplyOn
impl Hash for SnapStartApplyOn
source§impl Ord for SnapStartApplyOn
impl Ord for SnapStartApplyOn
source§fn cmp(&self, other: &SnapStartApplyOn) -> Ordering
fn cmp(&self, other: &SnapStartApplyOn) -> 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 SnapStartApplyOn
impl PartialEq for SnapStartApplyOn
source§fn eq(&self, other: &SnapStartApplyOn) -> bool
fn eq(&self, other: &SnapStartApplyOn) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd for SnapStartApplyOn
impl PartialOrd for SnapStartApplyOn
source§fn partial_cmp(&self, other: &SnapStartApplyOn) -> Option<Ordering>
fn partial_cmp(&self, other: &SnapStartApplyOn) -> 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 SnapStartApplyOn
impl StructuralPartialEq for SnapStartApplyOn
Auto Trait Implementations§
impl Freeze for SnapStartApplyOn
impl RefUnwindSafe for SnapStartApplyOn
impl Send for SnapStartApplyOn
impl Sync for SnapStartApplyOn
impl Unpin for SnapStartApplyOn
impl UnwindSafe for SnapStartApplyOn
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
source§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.