Struct Optional 

pub(crate) struct Optional<T>(pub(crate) Option<T>);

Tuple Fields

0: Option<T>

Trait Implementations

impl<T: Clone> Clone for Optional<T>

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

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Optional<T>

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

Formats the value using the given formatter.

impl<T> Default for Optional<T>

fn default() -> Optional<T>

Returns the “default value” for a type.

impl<T: Parse + Default> ParseArgument for Optional<T>

fn handle_argument<'a>( &mut self, meta: &ParseNestedMeta<'_>, key: &str, error: impl Into<ArgumentError<'a>>, ) -> Result<bool>

fn parse_argument<'a>( &mut self, meta: &ParseNestedMeta<'_>, key: &str, error: impl Into<ArgumentError<'a>>, ) -> Result<bool>

impl<T> ParseArgumentWith for Optional<T>

type With = T

fn handle_argument_with<'a>( &mut self, meta: &ParseNestedMeta<'_>, with: T, key: &str, error: impl Into<ArgumentError<'a>>, ) -> Result<bool>

fn parse_argument_with<'a>( &mut self, meta: &ParseNestedMeta<'_>, with: Self::With, key: &str, error: impl Into<ArgumentError<'a>>, ) -> Result<bool>

impl<T: Copy> Copy for Optional<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.