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