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extern crate devise;
extern crate proc_macro;
use ::devise::quote::quote;
use ::devise::syn;
use ::proc_macro::TokenStream;
mod parse;
mod codegen;
#[proc_macro_attribute]
pub fn fmt(attr: TokenStream, item: TokenStream) -> TokenStream {
let input = syn::parse_macro_input!(item as syn::ItemStruct);
let fmt = syn::parse_macro_input!(attr as parse::Fmt);
let s = &input;
let s_ident = &input.ident;
let s_build = codegen::struct_builder(s);
let s_parse = codegen::codegen(fmt);
let code = quote! {
#s
impl ::std::str::FromStr for #s_ident {
type Err = String;
fn from_str(s: &str) -> Result<#s_ident, String> {
#s_parse
Ok(#s_build)
}
}
};
code.into()
}