extern crate proc_macro;
extern crate proc_macro2;
extern crate quote;
extern crate syn;
use proc_macro::TokenStream;
use quote::quote;
#[proc_macro_attribute]
pub fn datatype(attr: TokenStream, item: TokenStream) -> TokenStream {
let attr = attr.to_string();
let item2 = item.clone();
let inp = syn::parse_macro_input!(item as syn::Item);
let item = item2.to_string();
let types = attr.split(" ");
let code: proc_macro2::TokenStream = types
.fold("".to_string(), |mut string, datatype| {
string.push_str(&item.clone().replace("f32", datatype));
string
})
.parse()
.unwrap();
let code = quote! {
#inp
#code
};
TokenStream::from(code)
}