translation.h

Go to the documentation of this file.

// Copyright (c) 2019 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
#ifndef BITCOIN_UTIL_TRANSLATION_H
#define BITCOIN_UTIL_TRANSLATION_H
 
#include <tinyformat.h>
 
#include <functional>
 
struct bilingual_str {
    std::string original;
    std::string translated;
 
    bilingual_str &operator+=(const bilingual_str &rhs) {
        original += rhs.original;
        translated += rhs.translated;
        return *this;
    }
 
    bool empty() const { return original.empty(); }
};
 
inline bilingual_str operator+(bilingual_str lhs, const bilingual_str &rhs) {
    lhs += rhs;
    return lhs;
}
 
inline bilingual_str Untranslated(std::string original) {
    return {original, original};
}
 
// Provide an overload of tinyformat::format which can take bilingual_str
// arguments.
namespace tinyformat {
// clang-format off
template <typename... Args>
bilingual_str format(const bilingual_str &fmt, const Args &...args) {
    const auto translate_arg{
        [](const auto &arg, [[maybe_unused]] bool translated) -> const auto & {
        if constexpr (std::is_same_v<decltype(arg), const bilingual_str &>) {
            return translated ? arg.translated : arg.original;
        } else {
            return arg;
        }
    }};
    return bilingual_str{
        tfm::format(fmt.original, translate_arg(args, false)...),
        tfm::format(fmt.translated, translate_arg(args, true)...)};
}
// clang-format on
} // namespace tinyformat
 
const extern std::function<std::string(const char *)> G_TRANSLATION_FUN;
 
inline bilingual_str _(const char *psz) {
    return bilingual_str{psz,
                         G_TRANSLATION_FUN ? (G_TRANSLATION_FUN)(psz) : psz};
}
 
#endif // BITCOIN_UTIL_TRANSLATION_H