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