Enum aws_sdk_quicksight::types::FontStyle
source · #[non_exhaustive]pub enum FontStyle {
Italic,
Normal,
Unknown(UnknownVariantValue),
}
Expand description
When writing a match expression against FontStyle
, 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 fontstyle = unimplemented!();
match fontstyle {
FontStyle::Italic => { /* ... */ },
FontStyle::Normal => { /* ... */ },
other @ _ if other.as_str() == "NewFeature" => { /* handles a case for `NewFeature` */ },
_ => { /* ... */ },
}
The above code demonstrates that when fontstyle
represents
NewFeature
, the execution path will lead to the second last match arm,
even though the enum does not contain a variant FontStyle::NewFeature
in the current version of SDK. The reason is that the variable other
,
created by the @
operator, is bound to
FontStyle::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 FontStyle::NewFeature
is defined.
Specifically, when fontstyle
represents NewFeature
,
the execution path will hit the second last match arm as before by virtue of
calling as_str
on FontStyle::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
Italic
Normal
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§
Trait Implementations§
source§impl Ord for FontStyle
impl Ord for FontStyle
source§impl PartialEq for FontStyle
impl PartialEq for FontStyle
source§impl PartialOrd for FontStyle
impl PartialOrd for FontStyle
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 FontStyle
impl StructuralEq for FontStyle
impl StructuralPartialEq for FontStyle
Auto Trait Implementations§
impl RefUnwindSafe for FontStyle
impl Send for FontStyle
impl Sync for FontStyle
impl Unpin for FontStyle
impl UnwindSafe for FontStyle
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.