genesis-impl 0.2.2

proc macro crate for genesis
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

use proc_macro2::TokenStream;
use quote::{quote, ToTokens};

use crate::input::*;

pub(crate) fn generate_code(input: &Input) -> TokenStream {
    let template_definition = generate_template_definition(input);

    let extra_attributes = input.attributes.iter().map(|attr| {
        let tokens = &attr.to_token_stream();
        quote! {
            #tokens
        }
    });

    quote! {
        #(#extra_attributes)*
        #template_definition
    }
}

fn generate_template_definition(input: &Input) -> TokenStream {
    let vis = &input.vis;
    let template_fields = input.components.iter().map(|c| {
        let ty = &c.field.ty;
        let name = &c.template_name;
        quote! {
            #vis #name: ::std::option::Option<#ty>,
        }
    });

    let name = &input.template_name;

    quote! {
        #[derive(Default)]
        #vis struct #name {
            #(#template_fields)*
        }
    }
}