Struct LitStr

pub struct LitStr { /* private fields */ }

A UTF-8 string literal: "foo".

Implementations

impl LitStr

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

pub fn value(&self) -> String

pub fn parse<T>(&self) -> Result<T, Error>

where T: Parse,

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>(&self, parser: F) -> Result<<F as Parser>::Output, Error>

where F: Parser,

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

fn clone(&self) -> LitStr

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for LitStr

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

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

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

fn parse(input: &ParseBuffer<'_>) -> Result<LitStr, Error>

impl PartialEq for LitStr

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl ToTokens for LitStr

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.

impl Eq for LitStr

impl Token for LitStr