Struct NoneValue

pub struct NoneValue;

A value that indicates the absence of any other value.

The none type has exactly one value: {none}.

When inserted into the document, it is not visible. This is also the value that is produced by empty code blocks. It can be joined with any value, yielding the other value.

Example

Not visible: #none

Trait Implementations

impl Clone for NoneValue

fn clone(&self) -> NoneValue

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for NoneValue

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

Formats the value using the given formatter.

impl Default for NoneValue

fn default() -> NoneValue

Returns the “default value” for a type.

impl FromValue for NoneValue

fn from_value(value: Value) -> Result<NoneValue, HintedString>

Try to cast the value into an instance of Self.

impl Hash for NoneValue

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl IntoValue for NoneValue

fn into_value(self) -> Value

Cast this type into a value.

impl NativeType for NoneValue

const NAME: &'static str = "none"

The type’s name.

fn data() -> &'static NativeTypeData

fn ty() -> Type

Get the type for the native Rust type.

impl Ord for NoneValue

fn cmp(&self, other: &NoneValue) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for NoneValue

fn eq(&self, other: &NoneValue) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for NoneValue

fn partial_cmp(&self, other: &NoneValue) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Reflect for NoneValue

fn input() -> CastInfo

Describe what can be cast into this value.

fn output() -> CastInfo

Describe what this value can be cast into.

fn castable(value: &Value) -> bool

Whether the given value can be converted to T.

fn error(found: &Value) -> HintedString

Produce an error message for an unacceptable value type.

impl Repr for NoneValue

fn repr(&self) -> EcoString

Return the debug representation of the value.

impl Serialize for NoneValue

fn serialize<S>( &self, serializer: S, ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for NoneValue

impl Eq for NoneValue

impl StructuralPartialEq for NoneValue