cpp-json/include/json/binder/json_direct_binder.hpp

//
//  json_direct_binder.hpp
//  json
//
//  Created by Sam Jaffe on 4/23/16.
//

#pragma once

#include "json_binder.hpp"

namespace json { namespace binder {
  template <typename T, typename E, typename = void> class direct_binder;

  template <typename T, typename E, typename = void>
  class forward_binder : public binder_impl<T> {
  public:
    forward_binder(E T::*p, binder<E> const & i) : ptr(p), impl(i) {}

    virtual binder_impl<T> * clone() const override {
      return new forward_binder(*this);
    }

    virtual void parse(T & val, char const *& data,
                       parser::options opts) const override {
      impl.parse(val.*ptr, data, opts);
    }

    virtual void write(T const & val, std::ostream & data) const override {
      impl.write(val.*ptr, data);
    }

  private:
    E T::*ptr;
    binder<E> impl;
  };

  template <typename T> class value_binder : public binder_impl<T> {
  private:
    struct detail {
      T value;
    };

  public:
    template <typename... Args>
    value_binder(Args &&... args) : impl(&detail::value, args...) {}

    virtual binder_impl<T> * clone() const override {
      return new value_binder(*this);
    }

    virtual void parse(T & val, char const *& data,
                       parser::options opts) const override {
      detail tmp;
      impl.parse(tmp, data, opts);
      val = std::move(tmp.value);
    }

    virtual void write(T const & val, std::ostream & data) const override {
      impl.write({val}, data);
    }

  private:
    direct_binder<detail, T> impl;
  };
}}