Enum AttrArg 

pub enum AttrArg {
    Ident(Symbol),
    Expr(ExprId),
}

One argument of an attribute.

Most attribute arguments are expressions, but a few take a bare identifier that must not be looked up as one: the printf in format(printf, 1, 2) names an archetype and the DI in mode(DI) names a machine mode, and neither is a variable. Treating them as expressions is how a compiler ends up reporting an undeclared identifier inside an attribute.

Variants

Ident(Symbol)

An identifier, kept as one.

Expr(ExprId)

An expression.

Trait Implementations

impl Clone for AttrArg

fn clone(&self) -> AttrArg

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for AttrArg

impl Debug for AttrArg

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

Formats the value using the given formatter.

impl Eq for AttrArg

impl PartialEq for AttrArg

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for AttrArg