demo-hack-impl 0.0.5

Demo of proc-macro-hack
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

extern crate proc_macro;
extern crate proc_macro_hack;
extern crate quote;
extern crate syn;

use proc_macro::TokenStream;
use proc_macro_hack::proc_macro_hack;
use quote::quote;
use syn::{parse_macro_input, Expr};

/// Add one to an expression.
#[proc_macro_hack]
pub fn add_one(input: TokenStream) -> TokenStream {
    let expr = parse_macro_input!(input as Expr);
    TokenStream::from(quote! {
        1 + (#expr)
    })
}