#[non_exhaustive]pub enum VpcLinkVersion {
V2,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against VpcLinkVersion
, 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 vpclinkversion = unimplemented!();
match vpclinkversion {
VpcLinkVersion::V2 => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when vpclinkversion
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant VpcLinkVersion::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
VpcLinkVersion::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 VpcLinkVersion::NewFeature
is defined.
Specifically, when vpclinkversion
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on VpcLinkVersion::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.
The version of the VPC link.
Variants (Non-exhaustive)§
This enum is marked as non-exhaustive
V2
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for VpcLinkVersion
impl AsRef<str> for VpcLinkVersion
source§impl Clone for VpcLinkVersion
impl Clone for VpcLinkVersion
source§fn clone(&self) -> VpcLinkVersion
fn clone(&self) -> VpcLinkVersion
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for VpcLinkVersion
impl Debug for VpcLinkVersion
source§impl From<&str> for VpcLinkVersion
impl From<&str> for VpcLinkVersion
source§impl FromStr for VpcLinkVersion
impl FromStr for VpcLinkVersion
source§impl Hash for VpcLinkVersion
impl Hash for VpcLinkVersion
source§impl Ord for VpcLinkVersion
impl Ord for VpcLinkVersion
source§fn cmp(&self, other: &VpcLinkVersion) -> Ordering
fn cmp(&self, other: &VpcLinkVersion) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<VpcLinkVersion> for VpcLinkVersion
impl PartialEq<VpcLinkVersion> for VpcLinkVersion
source§fn eq(&self, other: &VpcLinkVersion) -> bool
fn eq(&self, other: &VpcLinkVersion) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<VpcLinkVersion> for VpcLinkVersion
impl PartialOrd<VpcLinkVersion> for VpcLinkVersion
source§fn partial_cmp(&self, other: &VpcLinkVersion) -> Option<Ordering>
fn partial_cmp(&self, other: &VpcLinkVersion) -> 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 VpcLinkVersion
impl StructuralEq for VpcLinkVersion
impl StructuralPartialEq for VpcLinkVersion
Auto Trait Implementations§
impl RefUnwindSafe for VpcLinkVersion
impl Send for VpcLinkVersion
impl Sync for VpcLinkVersion
impl Unpin for VpcLinkVersion
impl UnwindSafe for VpcLinkVersion
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.