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