disp 0.1.0

derive Display from Debug
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41

//use derive_display_from_debug::Display;

#[cfg(test)]
mod tests {
    #[test]
    fn it_works() {
        let result = 2 + 2;
        assert_eq!(result, 4);
    }

    /* can't use a  deddere
    use super::*;
    use std::fmt::Display;

    #[derive(Debug, Display)]
    struct NewStruct {}
    */
}

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()
}