architect-derive 0.4.0

Architect.xyz Trading Platform API, proc-macros
Documentation 
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// copied from https://github.com/jofas/display_json/blob/master/src/lib.rs

use proc_macro::TokenStream;
use quote::quote;
use syn::{
    parse_macro_input, punctuated::Punctuated, token::Comma, DeriveInput, GenericParam,
    Generics, TypeParamBound,
};

pub fn derive_from_str_json(input: TokenStream) -> TokenStream {
    let input = parse_macro_input!(input as DeriveInput);
    let name = &input.ident;
    let generics = &input.generics;
    let params = deserialize_in_generics(generics);
    let result = quote! {
        impl<#params> std::str::FromStr for #name #generics {
            type Err = serde_json::Error;

            fn from_str(s: &str) -> Result<Self, Self::Err> {
              serde_json::from_str(s)
            }
        }
    };
    TokenStream::from(result)
}

fn deserialize_in_generics(g: &Generics) -> Punctuated<GenericParam, Comma> {
    let mut params = Punctuated::<GenericParam, Comma>::new();

    for param in g.params.iter() {
        let param = match param {
            GenericParam::Type(typ) => {
                let mut typ = typ.clone();
                typ.bounds.push(TypeParamBound::Trait(
                    syn::parse_str("serde::de::DeserializeOwned").unwrap(),
                ));
                GenericParam::Type(typ.clone())
            }
            _ => param.clone(),
        };
        params.push(param);
    }

    params
}