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