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