Enum SpannedOption 

pub enum SpannedOption<T> {
    Some(T),
    None(Span),
}

An Option-like enum that tracks the source location of an absent value.

This type is used to represent comma-separated items that can be omitted.

• The Some variant holds the parsed item T. The item T itself is expected to be a spanned type.
• The None variant holds the Span of the empty slot, typically the location of the comma separator.

Variants

Some(T)

None(Span)

Implementations

impl<T> SpannedOption<T>

pub fn is_none(&self) -> bool

Returns true if the SpannedOption is None.

pub fn is_some(&self) -> bool

Returns true if the SpannedOption is Some.

pub fn unspan(self) -> Option<T>

Converts the SpannedOption into an Option.

pub fn map<U, F>(self, f: F) -> SpannedOption<U>

where F: FnOnce(T) -> U,

Maps the SpannedOption to a new SpannedOption.

pub fn as_ref(&self) -> SpannedOption<&T>

Converts from &SpannedOption<T> to SpannedOption<&T>.

impl<T: Deref> SpannedOption<T>

pub fn as_deref(&self) -> SpannedOption<&<T as Deref>::Target>

Converts from SpannedOption<T> (or &SpannedOption<T>) to SpannedOption<&T::Target>.

Trait Implementations

impl<T: Clone> Clone for SpannedOption<T>

fn clone(&self) -> SpannedOption<T>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for SpannedOption<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> From<SpannedOption<T>> for Option<T>

fn from(spanned: SpannedOption<T>) -> Self

Converts to this type from the input type.

impl<T: Copy> Copy for SpannedOption<T>

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.