Struct MetaNameValueInvalidExpr 

pub struct MetaNameValueInvalidExpr {
    pub path: Path,
    pub eq_token: Eq,
    pub value: TokenStream,
    pub error: Error,
}

Represents a name-value attribute like foo = ... where we failed to parse the RHS (...) as a syn::Expr.

For example:

#[processor(vis = pub(crate))]

We first try to parse that vis = pub(crate) into a syn::Meta::NameValue. This requires the RHS (pub(crate)) to be a valid syn::Expr.

Because pub(crate) is not a valid expression, we store the TokenStream corresponding to pub(crate) in this struct, as well as the original syn::Error obtained from <syn::Expr as Parse>::parse(quote!(pub(crate)))

This syn::Error is used for good error messages when a type does not implement [FromMeta::from_invalid_expr], as the default implementation of that function just returns the stored error.

Fields

path: Path

In vis = pub(crate), this is the vis

eq_token: Eq

In vis = pub(crate), this is the =

value: TokenStream

The original input that we tried to parse as a syn::Expr, but failed

In vis = pub(crate), this is pub(crate)

error: Error

The error that we got from failing to parse input as a syn::Expr

In vis = pub(crate), this is:

<syn::Expr as syn::parse::Parse>::parse(quote!(pub(crate))).unwrap_err()

Trait Implementations

impl Clone for MetaNameValueInvalidExpr

fn clone(&self) -> MetaNameValueInvalidExpr

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MetaNameValueInvalidExpr

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

Formats the value using the given formatter.

impl Eq for MetaNameValueInvalidExpr

impl PartialEq for MetaNameValueInvalidExpr

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

Equality operator ==.

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

Inequality operator !=.

impl ToTokens for MetaNameValueInvalidExpr

fn to_tokens(&self, tokens: &mut TokenStream)

Write self to the given TokenStream.

fn to_token_stream(&self) -> TokenStream

Convert self directly into a TokenStream object.

fn into_token_stream(self) -> TokenStream

where Self: Sized,

Convert self directly into a TokenStream object.