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extern crate proc_macro;
use proc_macro::TokenStream;
use quote::quote;
#[proc_macro_derive(Display)]
pub fn display_derive(input: TokenStream) -> TokenStream {
let ast = syn::parse(input).expect("TokenStream could not be parsed");
impl_display_derive(&ast)
}
fn impl_display_derive(ast: &syn::DeriveInput) -> TokenStream {
let name = &ast.ident;
let gen = quote! {
impl Display for #name {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{:?}", self)
}
}
};
gen.into()
}