Enum aws_sdk_ec2::types::ImageTypeValues
source · #[non_exhaustive]pub enum ImageTypeValues {
Kernel,
Machine,
Ramdisk,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against ImageTypeValues
, 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 imagetypevalues = unimplemented!();
match imagetypevalues {
ImageTypeValues::Kernel => { /* ... */ },
ImageTypeValues::Machine => { /* ... */ },
ImageTypeValues::Ramdisk => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when imagetypevalues
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant ImageTypeValues::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
ImageTypeValues::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 ImageTypeValues::NewFeature
is defined.
Specifically, when imagetypevalues
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on ImageTypeValues::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
Kernel
Machine
Ramdisk
Unknown(UnknownVariantValue)
Unknown
contains new variants that have been added since this code was generated.
Implementations§
Trait Implementations§
source§impl AsRef<str> for ImageTypeValues
impl AsRef<str> for ImageTypeValues
source§impl Clone for ImageTypeValues
impl Clone for ImageTypeValues
source§fn clone(&self) -> ImageTypeValues
fn clone(&self) -> ImageTypeValues
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl Debug for ImageTypeValues
impl Debug for ImageTypeValues
source§impl From<&str> for ImageTypeValues
impl From<&str> for ImageTypeValues
source§impl FromStr for ImageTypeValues
impl FromStr for ImageTypeValues
source§impl Hash for ImageTypeValues
impl Hash for ImageTypeValues
source§impl Ord for ImageTypeValues
impl Ord for ImageTypeValues
source§fn cmp(&self, other: &ImageTypeValues) -> Ordering
fn cmp(&self, other: &ImageTypeValues) -> Ordering
1.21.0 · source§fn max(self, other: Self) -> Selfwhere
Self: Sized,
fn max(self, other: Self) -> Selfwhere Self: Sized,
source§impl PartialEq<ImageTypeValues> for ImageTypeValues
impl PartialEq<ImageTypeValues> for ImageTypeValues
source§fn eq(&self, other: &ImageTypeValues) -> bool
fn eq(&self, other: &ImageTypeValues) -> bool
self
and other
values to be equal, and is used
by ==
.source§impl PartialOrd<ImageTypeValues> for ImageTypeValues
impl PartialOrd<ImageTypeValues> for ImageTypeValues
source§fn partial_cmp(&self, other: &ImageTypeValues) -> Option<Ordering>
fn partial_cmp(&self, other: &ImageTypeValues) -> 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 ImageTypeValues
impl StructuralEq for ImageTypeValues
impl StructuralPartialEq for ImageTypeValues
Auto Trait Implementations§
impl RefUnwindSafe for ImageTypeValues
impl Send for ImageTypeValues
impl Sync for ImageTypeValues
impl Unpin for ImageTypeValues
impl UnwindSafe for ImageTypeValues
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.