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