kompact_actor_derive/
lib.rs

1#![recursion_limit = "128"]
2extern crate proc_macro;
3use proc_macro::TokenStream;
4use proc_macro2::TokenStream as TokenStream2;
5use quote::quote;
6use syn::{parse_macro_input, DeriveInput};
7
8/// A macro to derive empty actor implementations
9///
10/// Use this macro if you only care about the component model mechanics for your type.
11///
12/// Implementations derived using this macro have message type `Never` (or `!` if you prefer).
13/// Whenever they receive a network message, they simply log a warning.
14#[proc_macro_derive(Actor)]
15pub fn actor(input: TokenStream) -> TokenStream {
16    // Parse the input stream
17    let ast = parse_macro_input!(input as DeriveInput);
18
19    // Build the impl
20    let gen = impl_actor(&ast);
21
22    //println!("Derived code:\n{}", gen.clone().into_string());
23
24    // Return the generated impl
25    gen.into()
26}
27
28fn impl_actor(ast: &syn::DeriveInput) -> TokenStream2 {
29    let name = &ast.ident;
30    if let syn::Data::Struct(_) = ast.data {
31        let generics = &ast.generics;
32        let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
33
34        quote! {
35            impl #impl_generics ActorRaw for #name #ty_generics #where_clause {
36
37                type Message = Never;
38
39                fn receive(&mut self, env: MsgEnvelope<Self::Message>) -> Handled {
40                    warn!(self.log(), "Got msg, but component isn't handling any: {:?}", env);
41                    Handled::Ok
42                }
43            }
44        }
45    } else {
46        //Nope. This is an Enum. We cannot handle these!
47        panic!("#[derive(Actor)] is only defined for structs, not for enums!");
48    }
49}
kompact_actor_derive/lib.rs

kompact_actor_derive/
lib.rs
