youxi_codegen/
lib.rs

1extern crate proc_macro;
2use proc_macro2::TokenStream;
3use quote::quote;
4use quote::*;
5
6macro_rules! state_attribute {
7  ($fn:ident, $implement:ident, $derive:ident) => {
8    #[proc_macro_attribute]
9    pub fn $fn(attr: proc_macro::TokenStream, item: proc_macro::TokenStream) -> proc_macro::TokenStream {
10      let attr = TokenStream::from(attr);
11      let ast: syn::ItemFn = syn::parse(item).unwrap();
12      let mut tokens = TokenStream::new();
13
14      ast.block.to_tokens(&mut tokens);
15      let expanded = quote!{
16        impl $implement for #attr {
17          fn $fn(&mut self) #tokens
18        }
19      };
20      proc_macro::TokenStream::from(expanded)
21    }
22
23    #[proc_macro_derive($implement)]
24    pub fn $derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
25      let ast: syn::DeriveInput = syn::parse(input).unwrap();
26      let name = &ast.ident;
27      let expanded = quote! {
28        impl $implement for #name {
29          fn $fn(&mut self) {}
30        }
31      };
32      proc_macro::TokenStream::from(expanded)
33    }
34  };
35}
36
37state_attribute!(on_start, OnStart, derive_on_start);
38state_attribute!(on_stop, OnStop, derive_on_stop);
39
40#[proc_macro_attribute]
41pub fn on_event(attr: proc_macro::TokenStream, item: proc_macro::TokenStream) -> proc_macro::TokenStream {
42  let attr = TokenStream::from(attr);
43  let ast: syn::ItemFn = syn::parse(item).unwrap();
44  let mut tokens = TokenStream::new();
45  ast.block.to_tokens(&mut tokens);
46  let expanded = quote!{
47    impl OnEvent for #attr {
48      fn on_event(&mut self, window: &mut Window, events: &mut EventsLoop) #tokens
49    }
50  };
51  proc_macro::TokenStream::from(expanded)
52}
53
54#[proc_macro_derive(OnEvent)]
55pub fn derive_on_event(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
56  let ast: syn::DeriveInput = syn::parse(input).unwrap();
57  let name = &ast.ident;
58  let expanded = quote! {
59    impl OnEvent for #name {
60      fn on_event(&mut self, window: &mut Window, events: &mut EventsLoop) {}
61    }
62  };
63  proc_macro::TokenStream::from(expanded)
64}
65
66#[proc_macro_attribute]
67pub fn on_update(attr: proc_macro::TokenStream, item: proc_macro::TokenStream) -> proc_macro::TokenStream {
68  let attr = TokenStream::from(attr);
69  let ast: syn::ItemFn = syn::parse(item).unwrap();
70  let mut tokens = TokenStream::new();
71  ast.block.to_tokens(&mut tokens);
72  let expanded = quote!{
73    impl OnUpdate for #attr {
74      fn on_update(&mut self, elapsed: u128, window: &mut Window) #tokens
75    }
76  };
77  proc_macro::TokenStream::from(expanded)
78}
79
80#[proc_macro_derive(OnUpdate)]
81pub fn derive_on_update(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
82  let ast: syn::DeriveInput = syn::parse(input).unwrap();
83  let name = &ast.ident;
84  let expanded = quote! {
85    impl OnUpdate for #name {
86      fn on_update(&mut self, elapsed: u128, window: &mut Window) {}
87    }
88  };
89  proc_macro::TokenStream::from(expanded)
90}
youxi_codegen/lib.rs

youxi_codegen/
lib.rs
