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