Enum AllowableValue

pub enum AllowableValue<'src> {
    Any,
    Empty,
    Effective(InterpretedValue<'src>),
    Implied(&'static str),
}

Allowable values for the attribute.

Variants

Any

Any value is accepted.

Empty

Indicates the attribute doesn’t require an explicit value. The attribute is simply turned on by being set.

Effective(InterpretedValue<'src>)

In some cases, an empty value is interpreted by the processor as one of the allowable non-empty values. This effective value is prefixed with an equals sign and enclosed in square brackets (e.g., [=auto]). An attribute reference will resolve to an empty value rather than the effective value.

Implied(&'static str)

Built-in attributes that are not set may have an implied value. The implied value is enclosed in parentheses (e.g., (attributes)). An implied value can’t be resolved using an attribute reference.

Trait Implementations

impl<'src> Clone for AllowableValue<'src>

fn clone(&self) -> AllowableValue<'src>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'src> Debug for AllowableValue<'src>

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

Formats the value using the given formatter.

impl<'src> PartialEq for AllowableValue<'src>

fn eq(&self, other: &AllowableValue<'src>) -> bool

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

const 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<'src> Eq for AllowableValue<'src>

impl<'src> StructuralPartialEq for AllowableValue<'src>