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extern crate proc_macro;
use proc_macro::TokenStream;
use syn::{parse_macro_input, DeriveInput};
#[proc_macro_derive(JsonResponder)]
pub fn responder_derive(input: TokenStream) -> TokenStream {
let ast = parse_macro_input!(input as DeriveInput);
let struct_name = &ast.ident.to_string();
let generic_impl = "
impl actix_web::Responder for {} {
type Body = actix_web::body::BoxBody;
fn respond_to(self, _: &actix_web::HttpRequest) -> actix_web::HttpResponse<Self::Body> {
match serde_json::to_string(&self) {
Err(err) => actix_web::HttpResponse::from_error(err),
Ok(value) => actix_web::HttpResponse::Ok().content_type(\"application/json\").body(value)
}
}
}
";
generic_impl
.replace("{}", struct_name.as_str())
.parse()
.unwrap()
}