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#![doc(html_root_url = "https://docs.rs/wasm-bindgen-macro-support/0.2")]
extern crate proc_macro2;
extern crate quote;
#[macro_use]
extern crate syn;
#[macro_use]
extern crate wasm_bindgen_backend as backend;
extern crate wasm_bindgen_shared as shared;
pub use parser::BindgenAttrs;
use parser::MacroParse;
use backend::{Diagnostic, TryToTokens};
use proc_macro2::TokenStream;
mod parser;
pub fn expand(attr: TokenStream, input: TokenStream) -> Result<TokenStream, Diagnostic> {
let item = syn_parse::<syn::Item>(input, "rust item")?;
let opts = syn_parse(attr, "#[wasm_bindgen] attribute options")?;
let mut tokens = proc_macro2::TokenStream::new();
let mut program = backend::ast::Program::default();
item.macro_parse(&mut program, (Some(opts), &mut tokens))?;
program.try_to_tokens(&mut tokens)?;
Ok(tokens)
}
fn syn_parse<T: syn::synom::Synom>(tokens: TokenStream, name: &str) -> Result<T, Diagnostic> {
syn::parse2(tokens.clone())
.map_err(|err| {
Diagnostic::span_error(&tokens, format!("error parsing {}: {}", name, err))
})
}