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