luban_macros 0.1.1

luban macros.
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

extern crate quote;
use proc_macro::TokenStream;
use quote::{format_ident, quote};
use syn::{parse_macro_input, DeriveInput};

#[proc_macro_derive(EnumFromNum)]
pub fn enum_from_num(input: TokenStream) -> TokenStream {
    let input = parse_macro_input!(input as DeriveInput);
    let ty_name = &input.ident;


    let tokens = vec![
        format_ident!("i64"),
        format_ident!("i16"),
        format_ident!("i8"),
        format_ident!("isize"),
        format_ident!("u64"),
        format_ident!("u32"),
        format_ident!("u16"),
        format_ident!("u8"),
        format_ident!("usize"),
        format_ident!("f64"),
        format_ident!("f32"),
    ];
    let expanded = quote! {
        #(
            impl From<#tokens> for #ty_name {
                fn from(value: #tokens) -> Self {
                    (value as i32).into()
                }
            }            
        )*
    };
    
    TokenStream::from(expanded)
}