Struct syn::LitStr

pub struct LitStr { /* private fields */ }

A UTF-8 string literal: "foo".

Implementations

impl LitStr

pub fn new(value: &str, span: Span) -> Self

pub fn value(&self) -> String

pub fn parse<T: Parse>(&self) -> Result<T>

Available on crate feature parsing only.

Parse a syntax tree node from the content of this string literal.

All spans in the syntax tree will point to the span of this LitStr.

Example

use syn::{Attribute, Error, Expr, Lit, Meta, Path, Result};

// Parses the path from an attribute that looks like:
//
//     #[path = "a::b::c"]
//
// or returns `None` if the input is some other attribute.
fn get_path(attr: &Attribute) -> Result<Option<Path>> {
    if !attr.path().is_ident("path") {
        return Ok(None);
    }

    if let Meta::NameValue(meta) = &attr.meta {
        if let Expr::Lit(expr) = &meta.value {
            if let Lit::Str(lit_str) = &expr.lit {
                return lit_str.parse().map(Some);
            }
        }
    }

    let message = "expected #[path = \"...\"]";
    Err(Error::new_spanned(attr, message))
}

pub fn parse_with<F: Parser>(&self, parser: F) -> Result<F::Output>

Available on crate feature parsing only.

Invoke parser on the content of this string literal.

All spans in the syntax tree will point to the span of this LitStr.

Example

let lit_str: LitStr = /* ... */;

// Parse a string literal like "a::b::c" into a Path, not allowing
// generic arguments on any of the path segments.
let basic_path = lit_str.parse_with(syn::Path::parse_mod_style)?;

pub fn span(&self) -> Span

pub fn set_span(&mut self, span: Span)

pub fn suffix(&self) -> &str

pub fn token(&self) -> Literal

Trait Implementations

impl Clone for LitStr

Available on crate feature clone-impls only.

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for LitStr

Available on crate feature extra-traits only.

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

Formats the value using the given formatter.

impl From<LitStr> for Lit

fn from(e: LitStr) -> Lit

Converts to this type from the input type.

impl Hash for LitStr

Available on crate feature extra-traits only.

fn hash<H>(&self, state: &mut H)where H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Parse for LitStr

Available on crate feature parsing only.

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

impl PartialEq<LitStr> for LitStr

Available on crate feature extra-traits only.

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

This method tests for self and other values to be equal, and is used by ==.

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.

impl ToTokens for LitStr

Available on crate feature printing only.

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) -> TokenStreamwhere Self: Sized,

Convert self directly into a TokenStream object.

impl Eq for LitStr

Available on crate feature extra-traits only.

impl Token for LitStr