icu.h

Go to the documentation of this file.

/* *****************************************************************************
 * kblib is a general utility library for C++14 and C++17, intended to provide
 * performant high-level abstractions and more expressive ways to do simple
 * things.
 *
 * Copyright (c) 2021 killerbee
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 * ****************************************************************************/
 
#ifndef KBLIB_ICU_H
#define KBLIB_ICU_H
 
#include "tdecl.h"
 
#include <ostream>
#include <string>
#include <typeinfo>
#include <unicode/unistr.h>
 
namespace kblib {
 
template <typename string = std::string>
auto toUTF8(const icu::UnicodeString& s) -> string {
   string res;
   return s.toUTF8String(res);
}
 
template <typename string>
auto fromUTF8(string s) -> icu::UnicodeString {
   return icu::UnicodeString::fromUTF8(s);
}
 
template <typename string = std::u32string>
auto toUTF32(const icu::UnicodeString& s) -> string {
   string res(s.countChar32(), '\0');
   UErrorCode ec{U_ZERO_ERROR};
   s.toUTF32(&res[0], res.size(), ec);
   if (U_FAILURE(ec)) {
      // silence warnings about ec not being a temporary
      throw UErrorCode{ec};
   }
   return res;
}
 
template <typename string>
auto fromUTF32(string s) -> icu::UnicodeString {
   return icu::UnicodeString::fromUTF32(s.data(), s.length());
}
 
namespace icu_str_ops {
 
   inline auto operator<<(std::ostream& os, const icu::UnicodeString& str)
       -> std::ostream& {
      return os << toUTF8(str);
   }
 
   inline auto operator+(std::string lhs, const icu::UnicodeString& str)
       -> std::string {
      return str.toUTF8String(lhs);
   }
 
   inline auto operator+(icu::UnicodeString lhs, const std::string& rhs)
       -> icu::UnicodeString {
      return lhs += fromUTF8(rhs);
   }
} // namespace icu_str_ops
 
template <typename T>
auto fromStr(const icu::UnicodeString& val, const char* type = typeid(T).name())
    -> T {
   return fromStr<T>(toUTF8(val), type);
}
 
} // namespace kblib
 
#endif // KBLIB_ICU_H