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