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