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extern crate proc_macro;
use proc_macro::TokenStream;
use quote::quote;
use syn;
#[proc_macro_derive(GameObject)]
pub fn game_object_derive(input: TokenStream) -> TokenStream {
let ast = syn::parse(input).unwrap();
impl_game_object(&ast)
}
fn impl_game_object(ast: &syn::DeriveInput) -> TokenStream {
let name = &ast.ident;
let gen = quote! {
impl GameObject for #name {
unsafe fn from_raw(address: *const usize) -> Option<*mut #name> {
let ptr = address as *mut Self;
if (ptr as *mut usize).is_null() {
return None
}
Some(ptr)
}
}
};
gen.into()
}