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