std::towctrans (3) - Linux Manuals

std::towctrans: std::towctrans


std::towctrans - std::towctrans


Defined in header <cwctype>
std::wint_t towctrans( std::wint_t wc, std::wctrans_t desc );

Maps the wide character wc using the current C locale's LC_CTYPE mapping category identified by desc.
If the value of ch is neither representable as a wchar_t nor equal to the value of the macro WEOF, the behavior is undefined.


ch - the wide character to map
desc - the LC_CTYPE mapping, obtained from a call to std::wctrans

Return value

The mapped value of ch using the mapping identified by desc in LC_CTYPE facet of the current C locale.


The following example demonstrates katakana to hiragana character mapping
// Run this code

  #include <clocale>
  #include <cwctype>
  #include <iostream>
  #include <algorithm>

  std::wstring tohira(std::wstring str)
      std::transform(str.begin(), str.end(), str.begin(), [](wchar_t c) {
           return std::towctrans(c, std::wctrans("tojhira"));
      return str;

  int main()
      std::setlocale(LC_ALL, "ja_JP.UTF-8");
      std::wstring kana = L"ヒラガナ";
      std::wcout << "katakana characters " << kana
                 << " are " << tohira(kana) << " in hiragana\n";


  katakana characters ヒラガナ are ひらがな in hiragana

See also

        looks up a character mapping category in the current C locale
wctrans (function)