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