#[non_exhaustive]pub enum IcebergNullOrder {
NullsFirst,
NullsLast,
Unknown(UnknownVariantValue),
}Expand description
When writing a match expression against IcebergNullOrder, 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 icebergnullorder = unimplemented!();
match icebergnullorder {
IcebergNullOrder::NullsFirst => { /* ... */ },
IcebergNullOrder::NullsLast => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}The above code demonstrates that when icebergnullorder represents
NewFeature, the execution path will lead to the second last match arm,
even though the enum does not contain a variant IcebergNullOrder::NewFeature
in the current version of SDK. The reason is that the variable other,
created by the @ operator, is bound to
IcebergNullOrder::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 IcebergNullOrder::NewFeature is defined.
Specifically, when icebergnullorder represents NewFeature,
the execution path will hit the second last match arm as before by virtue of
calling as_str on IcebergNullOrder::NewFeature also yielding "NewFeature".
Explicitly matching on the Unknown variant should
be avoided for two reasons:
- The inner data
UnknownVariantValueis 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
NullsFirst
NullsLast
Unknown(UnknownVariantValue)
Don’t directly match on 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 IcebergNullOrder
impl IcebergNullOrder
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 IcebergNullOrder
impl AsRef<str> for IcebergNullOrder
Source§impl Clone for IcebergNullOrder
impl Clone for IcebergNullOrder
Source§fn clone(&self) -> IcebergNullOrder
fn clone(&self) -> IcebergNullOrder
1.0.0 (const: unstable) · Source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source. Read moreSource§impl Debug for IcebergNullOrder
impl Debug for IcebergNullOrder
Source§impl Display for IcebergNullOrder
impl Display for IcebergNullOrder
Source§impl From<&str> for IcebergNullOrder
impl From<&str> for IcebergNullOrder
Source§impl FromStr for IcebergNullOrder
impl FromStr for IcebergNullOrder
Source§impl Hash for IcebergNullOrder
impl Hash for IcebergNullOrder
Source§impl Ord for IcebergNullOrder
impl Ord for IcebergNullOrder
Source§fn cmp(&self, other: &IcebergNullOrder) -> Ordering
fn cmp(&self, other: &IcebergNullOrder) -> Ordering
1.21.0 (const: unstable) · Source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere
Self: Sized,
Source§impl PartialEq for IcebergNullOrder
impl PartialEq for IcebergNullOrder
Source§fn eq(&self, other: &IcebergNullOrder) -> bool
fn eq(&self, other: &IcebergNullOrder) -> bool
self and other values to be equal, and is used by ==.Source§impl PartialOrd for IcebergNullOrder
impl PartialOrd for IcebergNullOrder
impl Eq for IcebergNullOrder
impl StructuralPartialEq for IcebergNullOrder
Auto Trait Implementations§
impl Freeze for IcebergNullOrder
impl RefUnwindSafe for IcebergNullOrder
impl Send for IcebergNullOrder
impl Sync for IcebergNullOrder
impl Unpin for IcebergNullOrder
impl UnsafeUnpin for IcebergNullOrder
impl UnwindSafe for IcebergNullOrder
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§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§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