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