hello_world_macro 0.0.1

Derive macro for hello world action
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22

extern crate proc_macro;

use proc_macro::TokenStream;
use syn::DeriveInput;

#[proc_macro_derive(HelloWorldDerive)]
pub fn hello_world_derive_macro(item: TokenStream) -> TokenStream {

    let ast: DeriveInput = syn::parse(item).unwrap();
    let ident = ast.ident;

    quote::quote! {
        impl #ident{
            pub fn run(&mut self) -> Result<(), String>{
                self.output = serde_json::to_value(format!("Hello {:?}", self.input.name))
                    .map_err(|e|e.to_string())?;
                Ok(())
            }
        }
    }
    .into()
}