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