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