Enum SpecArgValue 

pub enum SpecArgValue {
    Expr(Expr),
    Pat(Pat),
    Captures(Captures),
}

Each SpecArg’s value needs to be parsed in a way that allows invalid specs, e.g. forms which do not correspond directly to an syn::Expr in standard Rust.

NOTE: a SpecArgValue may hold unrelated syntactic elements such as [’syn::Expr], [syn::Pat`], and even fragments that would never appear as part of a valid Rust program.

Variants

Expr(Expr)

Pat(Pat)

Captures(Captures)

Implementations

impl SpecArgValue

pub fn try_into_expr(self) -> Result<Expr>

Return the Expr or fail.

pub fn try_into_pat(self) -> Result<Pat>

Return the Pat or fail.

pub fn try_into_captures(self) -> Result<Captures>

Return the Captures or fail.

Trait Implementations

impl Clone for SpecArgValue

fn clone(&self) -> SpecArgValue

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SpecArgValue

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

Formats the value using the given formatter.

impl ToTokens for SpecArgValue

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.