short_name.hpp

// Copyright (C) 2022 by Camden Mannett.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE or copy at https://www.boost.org/LICENSE_1_0.txt)
 
#pragma once
 
#include "arg_router/policy/policy.hpp"
#include "arg_router/utility/compile_time_string.hpp"
 
namespace arg_router::policy
{
template <typename S>
class short_name_t
{
public:
    using string_type = S;
 
    constexpr explicit short_name_t([[maybe_unused]] S str = {}) noexcept {}
 
    [[nodiscard]] constexpr static std::string_view short_name() noexcept { return S::get(); }
 
private:
    using full_name_type = AR_STRING_SV(config::short_prefix)::append_t<S>;
 
    static_assert(utility::utf8::count(short_name()) == 1, "Short name must only be one character");
    static_assert(full_name_type::get() != config::long_prefix,
                  "Short name with short prefix cannot match the long prefix");
};
 
template <char S>
constexpr auto short_name = short_name_t<AR_STRING(S)>{};
 
template <typename S>
constexpr auto short_name_utf8 = short_name_t<S>{};
 
template <typename S>
struct is_policy<short_name_t<S>> : std::true_type {
};
}  // namespace arg_router::policy