tailwag_macros 0.3.0

A collection of macros to support the tailwag crate
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

use darling::FromDeriveInput;
use proc_macro2::TokenStream;
use syn::{Data, DeriveInput};

#[derive(FromDeriveInput)]
#[darling(default, attributes(cli_args))]
struct Opts {
    message: String,
}

impl Default for Opts {
    fn default() -> Self {
        Opts {
            message: "Hello!".into(),
        }
    }
}

pub fn derive_impl(input: &DeriveInput) -> TokenStream {
    let &DeriveInput {
        ident: _,
        data,
        ..
    } = &&input;

    // Panic if we aren't using a Struct -- other types are not supported.
    let tokens = match data {
        Data::Struct(_data) => derive_struct(input),
        Data::Enum(_) => unimplemented!("Not implemented for enums"),
        Data::Union(_) => unimplemented!("Not implemented for unions"),
    };

    tokens
}