Enum aws_sdk_lexmodelsv2::types::SlotShape
source · #[non_exhaustive]pub enum SlotShape {
List,
Scalar,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against SlotShape
, 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 slotshape = unimplemented!();
match slotshape {
SlotShape::List => { /* ... */ },
SlotShape::Scalar => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when slotshape
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant SlotShape::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
SlotShape::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 SlotShape::NewFeature
is defined.
Specifically, when slotshape
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on SlotShape::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
List
Scalar
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl Ord for SlotShape
impl Ord for SlotShape
source§impl PartialEq for SlotShape
impl PartialEq for SlotShape
source§impl PartialOrd for SlotShape
impl PartialOrd for SlotShape
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 SlotShape
impl StructuralEq for SlotShape
impl StructuralPartialEq for SlotShape
Auto Trait Implementations§
impl RefUnwindSafe for SlotShape
impl Send for SlotShape
impl Sync for SlotShape
impl Unpin for SlotShape
impl UnwindSafe for SlotShape
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> 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,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
§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,
§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.