pub enum ReferenceExpr {
    Member {
        member: Member,
    },
    Expr {
        const_: Const,
        expr: Expr,
    },
}
Expand description

Expression that may be a constant or a reference to member field. Often used pattern is having attribute that refer to a field or constant expression.

Examples

/// Peeking first `const` token it decides to parse `Expr` variant.
let re: ReferenceExpr = parse_quote!(const 42);
assert_eq!(re, ReferenceExpr::Expr { const_: parse_quote!(const), expr: parse_quote!(42) });
/// Without `const` token it decides to parse `Member` variant.
let re: ReferenceExpr = parse_quote!(foo);
assert_eq!(re, ReferenceExpr::Member { member: format_ident!("foo").into() });

Variants§

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Member

Fields

§member: Member

Member reference.

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Expr

Fields

§const_: Const

Const token.

§expr: Expr

Constant expression

Trait Implementations§

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impl Clone for ReferenceExpr

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fn clone(&self) -> ReferenceExpr

Returns a copy of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for ReferenceExpr

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

Formats the value using the given formatter. Read more
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impl Parse for ReferenceExpr

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fn parse(input: ParseStream<'_>) -> Result<Self, Error>

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impl PartialEq<ReferenceExpr> for ReferenceExpr

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

This method tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl Eq for ReferenceExpr

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impl StructuralEq for ReferenceExpr

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impl StructuralPartialEq for ReferenceExpr

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for Twhere T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for Twhere T: ?Sized,

const: unstable · source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for Twhere T: ?Sized,

const: unstable · source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

const: unstable · source§

fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for Twhere U: From<T>,

const: unstable · source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for Twhere T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for Twhere U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
const: unstable · source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
const: unstable · source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.