1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
#![recursion_limit = "1024"]

#[macro_use]
extern crate quote;
#[macro_use]
extern crate syn;

extern crate proc_macro;
extern crate proc_macro2;

use proc_macro::TokenStream;
use syn::DeriveInput;

mod com_wrapper;

#[proc_macro_derive(ComWrapper, attributes(com))]
pub fn derive_com_wrapper(input: TokenStream) -> TokenStream {
    let input = parse_macro_input!(input as DeriveInput);
    com_wrapper::expand_com_wrapper(&input)
        .unwrap_or_else(compile_error)
        .into()
}

fn compile_error(message: String) -> proc_macro2::TokenStream {
    quote! {
        compile_error!(#message);
    }
}