#[non_exhaustive]pub enum ValidationSeverity {
Error,
Warning,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against ValidationSeverity
, 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 validationseverity = unimplemented!();
match validationseverity {
ValidationSeverity::Error => { /* ... */ },
ValidationSeverity::Warning => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when validationseverity
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ValidationSeverity::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
ValidationSeverity::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 ValidationSeverity::NewFeature
is defined.
Specifically, when validationseverity
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on ValidationSeverity::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
Error
Warning
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 ValidationSeverity
impl ValidationSeverity
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 ValidationSeverity
impl AsRef<str> for ValidationSeverity
source§impl Clone for ValidationSeverity
impl Clone for ValidationSeverity
source§fn clone(&self) -> ValidationSeverity
fn clone(&self) -> ValidationSeverity
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for ValidationSeverity
impl Debug for ValidationSeverity
source§impl Display for ValidationSeverity
impl Display for ValidationSeverity
source§impl From<&str> for ValidationSeverity
impl From<&str> for ValidationSeverity
source§impl FromStr for ValidationSeverity
impl FromStr for ValidationSeverity
source§impl Hash for ValidationSeverity
impl Hash for ValidationSeverity
source§impl Ord for ValidationSeverity
impl Ord for ValidationSeverity
source§fn cmp(&self, other: &ValidationSeverity) -> Ordering
fn cmp(&self, other: &ValidationSeverity) -> 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 ValidationSeverity
impl PartialEq for ValidationSeverity
source§impl PartialOrd for ValidationSeverity
impl PartialOrd for ValidationSeverity
impl Eq for ValidationSeverity
impl StructuralPartialEq for ValidationSeverity
Auto Trait Implementations§
impl Freeze for ValidationSeverity
impl RefUnwindSafe for ValidationSeverity
impl Send for ValidationSeverity
impl Sync for ValidationSeverity
impl Unpin for ValidationSeverity
impl UnwindSafe for ValidationSeverity
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<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)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.source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read more